Bitcoin is not stable, and it is digital, and banks don't have control over it. Once the price of Bitcoin drops so much, it will affect banks. Banks wouldn't risk their reputation by holding people's BTC. Maybe they are going to accept money from buyers who deal with someone selling and buying BTC, but I believe they don't want to be involve with this deal because crypto is risky and not stable. Maybe for USDT or any stable coin they might accept, but not for Bitcoin.
However, maybe depends on the jurisdiction since someone above said there are some banks, but here in my country, they don't accept Bitcoin since it is not widely used yet here.
Once the government allows banks to accept bitcoin deposits, that’s good to say that bitcoin is slowly getting centralized because once bitcoin is already within the hands of the banks, then we can say that the full control of the owner is no longer there, and that creates bigger advantage for banks while its kinda a loss for us owners.
However, if this will be adapted in the future, I don’t think that we can benefit from this, but will only put our bitcoin at risk, as there could be future stealing just like what’s happening inside the centralized exchanges. I just hope we can realize the real purpose of bitcoin, and that is financial freedom from the government and the banks.