In my opinion it's all the same because stablecoins and USD have the same nature and secondly they are centralized and we also don't have full control over our assets remember not your keys not your coins if you want to have full control over our coins maybe you have to store bitcoins in cold Our own wallet is more cross-border and easy to carry anywhere and just remember our own phrases remember there is no responsibility if our cassette is lost in the world of crypto currency
Stablecoins can also be stored in everyone's personal wallet, just like everyone keeps their Bitcoins quite safely, so in terms of how to store them, I don't think there will be much difference as long as both are in a fairly safe wallet. However, storing USD in a bank will of course be very different from storing stablecoins in our own wallet because USD in the bank can only be controlled by the bank, not by the actual owner.
So it is clear that there is a difference between these two things in terms of how to store it and also in terms of how to manage it and in terms of risk it will also be very different because a wallet that is not well guarded also has the possibility of being hacked by someone else. Meanwhile, banks will definitely be responsible if things happen that we don't want with our savings. As long as these things happen, it can be very logical for the bank to resolve them.
I don't seem to see things your way since when it comes to the USD in the bank, it's the only one that can assure you of the true $1=$1, stablecoins can't. This could be more painful if you are in dire need of money to be converted and there is a slight change in the price of the stablecoin against the USD, especially when the amount is much.
Secondly, your money in the bank is insured, even if there is any problem, you can be sure to get your money back. But no one might listen to you in case the wallet you store your stablecoin in is compromised. Unless I am using my stablecoin to trade, I would rather store my USD in the bank.