1) While Bitcoins are not controlled by an actual Government, etc, that also means that there is no official "customer service" for Bitcoin, especially when it comes to reimbursement; If you lose your private keys you are screwed, the coins are gone and therefore your money. Doesn't matter who you buy Bitcoins from, they can't help you at that point. Some companies have made this pretty avoidable though, by just allowing a username and password to sign into your Bitcoin wallet.
This is something I find bad as well. You can recover much more easily your bank account access, this is sure.
But as you wrote, this is not a real problem: people will just have to learn to backup their stuff.
I think this will be more and more automatic in the future.
2) Not enough businesses directly accept Bitcoin. While some big name companies do accept them, overall they aren't accepted at most online and local businesses at this point of writing. There are a lot of ways around this though just because of what Bitcoins CAN buy, which can be used to trade for the item you desire. For example if a local or online business accepts PayPal but not Bitcoin, it's easy to convert it.
Also this is true. But it's not a downside of Bitcoin itself, it's a downside of public reception.
Bitcoin adoption is growing. Slowly but steadily.
And we can bet in some good bumps in the future, when Banks will acknowledge that Bitcoin is not a scam or a ponzi (I still see some people comparing Bitcoin to a Ponzi).
Reputation is everything for Bitcoin. One adoption will get mainstream, this "problem" will be gone.
3) Bitcoin can be stolen through malware, social engineering, being robbed at gunpoint, etc. Malware can certainly be avoided, you can store your Bitcoins offline, encrypted, etc. on a malware free machine/device. Social engineering is unlikely, if you are familiar with Bitcoins, you are probably familiar with social engineering. Being robbed at gunpoint can hopefully be prevented by meeting in a busy coffee shop, etc.
Malware can steal your bank account credentials.
You can be robbed of fiat currency at gunpoint.
Bitcoin is no different in this from other money at all.
4) Bitcoin is not "user friendly". With terms like "Blockchain", "mBTC", "Private Key", "Hashing", "QR Code", etc. I can see where a lot of not tech-savvy people would be discouraged. It's clear that Satoshi didn't design Bitcoin to be used by everyone.
It's true that you need to know how to use computers to be completely at ease in using Bitcoin.
That will probably come with next generations.
People that are today past 50 years old are mostly cut out of the thing, they have to put quite some effort in understanding this stuff, unless they are IT specialists or using PCs since they born.
5) You can't pay your Government's taxes, fees, etc. in Bitcoin (at least I know in my country you can't).
You can, in some countries.
That goes with the shops anyway: the more Bitcoin will spread and get better reputation, the more countries will HAVE TO implement it as a media to pay taxes.
My points about downsides of Bitcoin:
1) lost bitcoins will not be recovered... EVER. You lose your keys, they're gone. This will, in the long range, bring to a scarcity.
Even worse: if governments ban Bitcoin, they can decide that any of these that will be recovered will be transferred on accounts of which keys will be thrown away.
That would be a quick way to destroy Bitcoin in its essence.
2) Bitcoin is NOT ENOUGH to cover the whole Earth wealth. Once you divide it by 21 million, there's not enough granularity to use it for everyday transactions.
Total Earth Wealth / all satoshi: $4'500'000'000'000'000 / 2'100'000'000'000'000 (21'000'000.00000000) = 2.14$
If the whole Earth would adopt Bitcoin, there won't be enough to go below 2$ value.
3) looks to me that transaction times are too long for everyday shopping. 1 or 2 confirmations should happen in less than 1 minute imho. Hope this gets better when more nodes will be added to the net.
