In case you didn’t know it already: banks are not really using ACID transaction on all operations that you would have thought they are. If that’s a surprise then let me tell you that ☞ not even Starbucks is using two-phase commit.
Distributed systems are changing the rules of the game:
the more distributed and decentralized a system is, the less likely it is that we can use transactions that span the entire system. That is certainly true for the banking system, apparently also true for systems inside banks, and in many other places. ACID transactions were invented for the mainframe, the world’s most centralized computing construct. But computing is not “one mainframe” any more I’m afraid as it was in the sixties.