Is Bitcoin’s Security Budget a Bigger Issue Than Most People Think?

[Antidote47k]

I’ve been going down a rabbit hole lately regarding Bitcoin’s long-term security budget, and it feels like it doesn’t get nearly as much attention as price action, ETFs, and institutional adoption, what happens when the block rewards eventually grind down to zero?
Whenever you bring this up, the standard response is always, "Don't worry, the fee market will take over and miners will stay incentivized."

But does that actually hold up?
Don't get me wrong, I get the counterargument: as Bitcoin grows, block space becomes incredibly scarce, and future settlement demand could make transactions valuable enough to sustain miners. But the reality is that the block subsidy keeps cutting in half every four years. Right now, transaction fees are still just a tiny drop in the bucket for miner revenue during normal periods. Most of their income still comes from that shrinking subsidy.
One thing that keeps bothering me is that every security-budget discussion eventually comes down to assumptions about future demand. We’re being asked to predict what users will be willing to pay for block space decades from now, and that feels like a much harder problem than many people admit.

To make things weirder, the ecosystem is aggressively pushing to move activity off-chain to Layer 2s and sidechains. It feels like a total paradox. For Bitcoin to scale globally, it needs L2s. But if L2s do their job too well and compress millions of transactions into just a few on-chain settlements, they might accidentally they might accidentally reduce fee pressure on the base layer pressure on the base. If there's no fee pressure, the security budget takes a massive hit.

Now, researchers like Pierre Rochard argue these fears are overblown. His point is that Bitcoin’s security isn't a fixed budget—it's a dynamic market. Between transaction fees, mining competition, and the difficulty adjustment, the network has built-in ways to adapt and stay resilient.

https://www.thestreet.com/crypto/markets/analyst-calls-bitcoins-security-budget-argument-a-category-error

But here’s what I can’t seem to reconcile: both sides agree the subsidy is disappearing. The disagreement is whether future demand for block space will naturally fill that gap.
Maybe it does. Maybe Bitcoin becomes such a valuable settlement network that users willingly pay for scarce block space. But that still feels more like a prediction than a guarantee.

Even if hash rate drops in the future, the difficulty adjustment keeps the network running. The real question is whether the cost of attacking the network remains sufficiently high relative to the value being secured.

Am I missing something obvious here, or is the security budget one of the biggest unanswered questions in Bitcoin’s long-term future?

[EluguHcman]

Am I missing something obvious here, or is the security budget one of the biggest unanswered questions in Bitcoin’s long-term future?

No I don't think there is anymore you are missing. You probably just choose to live there you are after much the doubts about the mining incentives has been cleared that the transaction fees will be profer the service to reward miners and so on the Blockchain network will still be secured with miners proceeding to validate transactions and adding new blocks after verification to the Blockchain.

Is there something different from the opinion of the Pierre Rochard which you have become aware of?
Or maybe you are probably overreacting like the other people who feels worried over the Bitcoin Blockchain network security. Just know that due to the competitions amongst miners, security modernity tends to spontaneously shift with resilience just as Pierre has also revealed in his own opinion.

[Stalker22]

Bitcoin is barely even 15 years old.  If I had to bet, I believe that fee market will develop further.   We are still a long way from the block subsidy hitting zero.

[MusaMohamed]

To make things weirder, the ecosystem is aggressively pushing to move activity off-chain to Layer 2s and sidechains. It feels like a total paradox. For Bitcoin to scale globally, it needs L2s. But if L2s do their job too well and compress millions of transactions into just a few on-chain settlements, they might accidentally they might accidentally reduce fee pressure on the base layer pressure on the base. If there's no fee pressure, the security budget takes a massive hit.

Bitcoin on-chain is very secured, the most secured blockchain, and if people want best security for their bitcoins and transactions, they will choose Bitcoin on chain for transactions and any business deals through Bitcoin blockchain.

Fortunately, during recent months, Bitcoin mempools have become very good for transactions with very low transaction fees, from 1 satoshi/vbyte to lower fee rates. For people who are not too technical, they can still enjoy 1 satoshi/vbyte fee rate but if they are ready to learn a little bit more technical steps, they can broadcast transactions with fee rates under 1 satoshi/vbyte.

How to make a bitcoin transaction and pay less than 1 sat/vByte
LoyceV's 0.1 sat/vbyte Electrum Server Adventure
DireWolfM14's Electrum SPV Server

You can discuss about current existence, development of Bitcoin side-chains in this topic Sidechain Observer - Bitcoin L2 Projects & current state of development.

[davis196]

To make things weirder, the ecosystem is aggressively pushing to move activity off-chain to Layer 2s and sidechains. It feels like a total paradox. For Bitcoin to scale globally, it needs L2s. But if L2s do their job too well and compress millions of transactions into just a few on-chain settlements, they might accidentally they might accidentally reduce fee pressure on the base layer pressure on the base. If there's no fee pressure, the security budget takes a massive hit.

I don't get the feeling, that the "ecosystem is aggressively pushing" second Layer solutions and sidechains. Some centralized crypto services are pushing sidechains and second Layer solutions, but there's nothing more than this. L2s are built on top of the Bitcoin Core blockchain transactions. L2s cannot impose pressure for reducing the transaction fees on the blockchain. If the amount of transactions on L2s is growing, the amount of transactions on the Bitcoin Core blockchain would also grow, which would push the transaction fees up.
What exactly do you mean by "security budget"? Can you elaborate more on this? I don't see any threats to Bitcoin's security right now.
AI and quantum computers are a future threat, not a current threat.

[Curious T]

It depends on how Bitcoin evolves within the next 100+ years. I have thought about this before, and that made me read up a little bit about it. When all blocks have been mined, I believe that a lot of miners will shut down, especially the small, private ones. The publicly traded bitcoin mining companies will have other things that generate income and cover costs, as we've already seen some companies expand to AI.

Currently, the total average payment in transaction fees is about $200,000 to $240,000 with a daily trading volume of 20 billion dollars. This is relatively little money when shared across different mining pools in the world that confirm transactions daily, but we must remember that Bitcoin has these numbers in about 17 years. Also, trading fees have been between $0.30 to $0.6 lately. By 114 years time, when all blocks have been mined, and any mining firms have shut down, assuming there are 20-30 left, and with transaction fees around a dollar, the daily transaction fees can go up to 3-5 million dollars. If 30 miners share that among themselves daily, that won't be little money.

All these are just speculations. It could be worse than this, it could be better than this, but I believe people would always find a way to minimize cost and make money, and as long as there is an opportunity to make money, it will incentivize people. It's still over a century away, so there is a lot of time for it to be figured out.