secp256k1 is the curve used in Elliptic Curve cryptography and SHA256 is the hash algorithm.
You can't "crack" the curve, you have to break the cryptography algorithm that is ECC. And if ECC is broken changing the hash algorithm doesn't change anything!
Also there is no SHA1024! If SHA-2 algorithm is broken and became weak then a new version of it should be used not necessarily a bigger digest size. ie version 3 or 4 of SHA not same SHA-2 with 1024-bit digest size.

Any proof or is it just the tinfoil hat talking?

If you use a fork to scratch your back, that doesn't mean a fork is no longer a kitchen utensil.

Wrong, that is the definition of fiat issued by government not the meaning of a currency. And you are using the dictionary definition here.
A currency is simply any medium of exchange. For example in a game the gold coins your character earns is a currency since you can use them as a medium of exchange in that world to buy goods such as an armor!

Your terminology is all over the place!
Altcoins or more precisely alternative cryptocurrencies are cryptocurrencies other than bitcoin. They don't "include" bitcoin.

No it does not mean that.
Saying bitcoin is a currency means you can use bitcoin as a medium of exchange

Well it's not that easy. There are a lot of unpredictable factors that are affecting the fees.
- We had the small hashrate drop recently that meant less blocks are found every day. Less blocks means less transactions are included in all blocks daily, hence more remain unconfirmed.
- We also had the price drop and each time there is a panic sell like that we see an increased number of transactions being made by users (sending coins to exchanges to sell or buying from exchanges and cashing it out or moving bitcoin between exchanges like from altcoin exchange back to bitcoin exchange to trade bitcoin).

So we have to predict when will the hashrate be back and we start getting the usual ~144 blocks per day (instead of current 106 in the past 24 hours). Difficulty adjustment will take care of that soon-ish (in 14 days) but we also have to predict whether price is going to stay stable like it did in the past 20 hours or will it start swinging again. Going up and down can again increase the fees.

Take a look at this chart showing the total size of transactions in mempool and their fees over the past week: https://jochen-hoenicke.de/queue/#BTC,1w,weight
As you can see the fees were already on the rise before the hashrate drama began due to price volatility. And your transaction that is paying 105 sat/vbytea is roughly at half the peak which is the high priority fee level.
So first the transactions paying higher fee than you have to be confirmed (about 20 vMB) and during that time no new transaction has to be created with higher fee so that the fees are lowered.

Dear newbie, welcome to the bitcoin world.
Bitcoin price going down 10% and currently sitting at 8% below its resistance is not called a "massive crash" it is tiny correction instead. A crash is if price went down at least 30% meaning if it had reached and stayed at $42k.

Dear newbie, if you really think that way then rush to the market and sell your bitcoin fast. We appreciate the weak hands giving us their coins at a discount.

Another article by idiots who have no idea how bitcoin and the blockchain technology works.
A centralized shitcoin with a massive premine is trying to increase the power of the owners of those premined coins in having more control over their centralized network so they have chosen an algorithm called Proof of Stake which not only rewards the richest people who own the most amount of that shitcoin (ie. the premine owners) but also gives them much bigger power in controlling the network at virtually no cost while earning money!
Bitcoin will never do such a thing.

1. Yes you can but it may be rejected by the noes that receive it.
3. When a transaction is not signalling RBF and a new transaction is received by the node that has the first one, that node considers the second tx to be a double spend and rejects it. This means if the node you are connected to has the first tx it will reject the second one and it won't propagate.
4. No need, you can use one wallet instance to do everything. The challenge you would be facing is to get the nodes to accept your double spent transaction.

That usually happens when people use bad wallets that aren't that user friendly. Try using Electrum.
If that's not the case, try learning how to work with the fee slider and read the mempool information from its charts like this one: https://jochen-hoenicke.de/queue/#0,24h

It is not possible to predict because it is essentially predicting how other people are going to act and that's not possible.
When price is volatile like these days there is always an increased number of transactions that create a competition (aka a fee market) that increases the fees.

Enable RBF on your transaction in the future (or use a wallet that lets you do that) so that you can bump the fees when your transactions get stuck and you are in a hurry to get them to confirm.
Since your tx fee is higher than 10 satoshi/byte you can use this accelerator for free: https://www.viabtc.com/tools/txaccelerator

Ethereum has never been a "currency" to begin with. By design ETH is a token or to be more precise it is fuel for smart contracts and nothing more.

Here is the flaw with this, why would something useless (according to you) have any value and grow?
Essentially that's what bitcoin is if you remove the currency aspect of it, it is some virtual numbers on the internet that we are wasting energy to find.

Although cheap transactions are desired but they are not the defining factor. Bitcoin is a currency and a very useful one at that because you can make a payment from anywhere in the world to anywhere in the world in matter of seconds without needing any third party's involvement or permission thanks to its decentralized nature.
This is exactly why bitcoin value keeps growing while altcoins' keep declining.

Highly unlikely because if we enter the bear market now that means the 12 year old ~4-year cycle is finally broken and consequently the bear market is also going to be different meaning it can only last a couple of months and the size of it is also going to be very small.
It wouldn't change anything about altcoins though, as they are still on the same dumping path as they were 5 years ago.

That is an entirely different matter which has nothing to do with your original question. And that's not a hack, I consider them more of a puzzle that were made (even if unintentionally and out of stupidity of the user) to be solved.

No they wouldn't, they still wouldn't be able to search a tiny portion of the entire space let alone find a single address with a balance.

First part is obvious but has nothing to do with the second part. You still can't know the range of a private key by seeing its public key.

So your entire theory is based on the fact that some early adopters decided to cash out a small percentage of their fortune because price is millions of times higher compared when they started?!

I'm assuming you mean "public key" not "public address" and you are wrong.
From the first bitcoin version (satoshi client 0.1.0) you could pay to pubkey hashes (ie. the P2PKH addresses we use today).
Here is the first P2PKH output from 16-Jan-2009
https://blockchair.com/bitcoin/transaction/6f7cf9580f1c2dfb3c4d5d043cdbb128c640e3f20161245aa7372e9666168516

Travelling to Uranus is easier than travelling to Neptune since Uranus is closer to Earth and still we can't do either.

This has always been a fake excuse by these developers to hide their malicious intents.
A closed source software can be exploited just as easily, and closing the source does NOT solve any problems. Look at how many exploits exist for Windows (ie. a closed source operating system) from the day it was created until today.
A closed source software can still have fake versions when all the malicious actor needs is the name of the wallet. People who don't verify what they download would get the fake version and lose their money all the same.

I think we have to first categorize the wallets.
Are we only comparing bitcoin wallets (wallets that only support bitcoin and absolutely nothing else). In that case I don't think closed source wallets are popular at all. We already have excellent open source bitcoin wallets for all platforms (desktop, iOS, Android,...) so closed source wallets have nothing to say here.
But when it comes to altcoin wallets, or more specifically multi-coin wallets where the user can store one or more altcoins in one wallet then the options shrink when it comes to good open source wallets. That is why they have gone towards closed source ones. For example Coinomi supports a very large number of altcoins and it has been letting people claim their shitcoin airdrops very easily while there is no open source wallet that could do the same. So obviously people are left with that bad option.

IMO it's just the last one plus that price couldn't break out above the next resistance and it pulled back a little. The rest of the drama were only putting fuel in the dropping price and led to a dump by market manipulators and eventually ended with a panic sell crashing the price bigger than usual, although the total drop size was still a small 10% drop.

If it were possible bitcoin wouldn't have survived past the first month let alone reach 12 years and a price of nearly $60,000. People have been trying to "hack" bitcoin for as long as it existed, eventually they all either give up when they finally understand it is not possible and some of them end up trying another method to steal other people's money like publishing a malicious application for others to download and infect their computer so that they can steal their money.

Do you know what the steps are? I mean is it just SHA2 hash/hmac + KDF or is there more including AES decryption and maybe address creation because I'm trying to figure out why you get ~7000 combinations per second only (it seems too low if the steps are the former).

You are already searching an impossible to find needle in a haystack so why are you making your own job harder by doing the search using the HD key derivation function? Why not just search for private keys and avoid all the extra overhead of the key derivation?!
If you were able to find a private key to steal other people's money (which you would never be able to) it doesn't matter if that key was derived from a master key or was found at random.

It is like wanting to find z from x+y=z but instead of first adding x and y you go ahead and compute pow, sqr, sqrt, cos, sin, sin^-1,... of both x and y then finally add x and y to find z.

It is neither simply because we have no way of actually measuring hashrate. We can only come up with a rough estimation and when the hashrate value is reported in small time frames such as a single day the error in that value is much greater compared to when it is estimated and reported in a longer period of time.

If you look at different hashrate charts in different sites (that don't copy each other) you can see the charts look the same but the values are not the same.
For example if you check https://bitinfocharts.com/comparison/bitcoin-hashrate.html#3m the average hashrate they have been reporting is about 130 Eh/s and the peak is 161 while the current low is 105 so you can say for the past 3 months the hashrate was 130 Eh/s ± 30 this is how rough the estimation is!
I don't see why the market is panicking over this though.

True, but fees are first and foremost affected by the price. We have had a shoot up to $64k over the past couple of days then a dump down to $60k. Also as price went below $60k (down to $51k and back) it attracts a lot of on-chain traffic and increases the fees.

There is no centralized authority to "pay" miners in a decentralized network. There is a reward that can be claimed for finding a new block that the miner has to claim themselves.
It basically works like this:
The miner builds a new block to start mining it, for that they include as many transactions as possible in that block while building a special transaction known as coinbase and in that transaction they pay themselves up to a certain amount that is determined based on the block height (for example block 679648 can have up to 6.25BTC reward) plus up to the sum of all transaction fees inside that block.

First of all the fee that exchanges charge when you buy bitcoin from them and when you withdraw it is not "bitcoin fee" it is actually "exchange fee" and it is always higher than the actual network fees.

Secondly $27 fee at $60k price is 0.00045000BTC which is $1.8 at $4k which is the price last time you posted in bitcointalk. This is exactly why you should never look at what you transact in terms of USD because you aren't transferring USD you are transferring bitcoin.
Besides, last time you were here the fees were so much higher than today's since there was a massive spam attack going on (in terms of satoshi per byte)! But obviously not in terms of USD since price was so much lower.

So in comparison you are paying less fee today and your confusion about fees is confusing.

In asymmetric cryptography (aka public-key cryptography) using Elliptic Curves or using Rivest–Shamir–Adleman algorithms, the private key is simply a number that we select at random in a certain range.

So to answer your question, if your RSA private key is selected at random and is in range to be a valid bitcoin private key (256 bit and between 1 and N) then you can use that "number" as your bitcoin private key.
But the issue is that since a 256 bit EC curve provides the same security as a 3072 bit RSA key and a 256-bit RSA keys aren't usually found, you can't convert the two. In simple terms there is a good chance that the RSA key you have is so much bigger than 256 bit.

If the input is random the output can be considered random too. Assuming the RSA key was selected randomly SHA256 of it is secure enough to be used as a private key assuming it is a valid value (within range).
The whole process is pointless though, since you can simply select a random bitcoin private key instead of selecting a random RSA key then hashing it. This is also risky since if you leak the RSA key you'd also leak the bitcoin key.

They can only do a small number of the total verification needed to validate a transaction though. Basically since the SPV clients don't have the UTXO set and there is no way of building it or downloading it without becoming a full node, they only rely on security of PoW so they only check the proof of work of each block header they download and then make sure the transaction is inside that block.
Otherwise they don't check double spends, signature validation, amount check, weight check, sigop count, script evaluation,... that a full node would do.