This is true. But there is another angle that I'm frankly disappointed in so called smart bitcoiners ignoring. So I'll explain it here.

There is a ton of money, fiat money that is in tax advantaged accounts in the US. This is money that can only be withdrawn to acquire bitcoin at a great lose in taxes to the state. There is an exception. In some cases it could be moved to an IRA with Unchained Capital. They will provide support and you can move this money into bitcoin where you hold your own keys in a multi-sig. However, this is not something most people are aware of. And, it isn't possible for some that have their money in fiat retirement systems.

So, the ETFs like buying Micro Strategy is a proxy. Its a better option than stocks as it does track the price of bitcoin. I don't know how much of this ETF money is coming from people that are writing checks and depositing it into their brokerage accounts but I know it can't be 100%. IMO that would be stupid. But if you have a pension or fiat locked into a retirement plan that the gov already has control over I would be hard pressed to say it is dumb to put some in an ETF.