It’s the very nature of the fiat system that makes this possible. There’s room for bailouts at many different layers of the system because fiat is not final settlement.
The world is going to converge on bitcoin as money because it’s finitely scarce. A byproduct of this is that the world is going to be using a money with an immutable ledger. There are no takebacks. This reality will impose greater personal responsibility on all the people who use it.
I don’t think all 8 billion people will hold private keys. But all 8 billion people will have to learn how to use bitcoin in a trust-minimized way.