Log recovery is definitely possible and theoretically meaningful Completely without losing data. MySQL probably can’t do it, at least it has to be at Oracle level (why don’t banks use MySQL)?
In addition, you have to spend a lot of money on hardware. Even if two nodes in your hot backup fail at the same time, it is not impossible. In this case, the best server, two power supplies, and the computer room must be specially designed
In short, it’s just two words: throw money

I just thought of the word "complete" and there is still a problem
Even if the bank spends so much money, for the so-called completeness, don’t you still have paper records for every cash operation at a business outlet?
In terms of reliability, don’t look down on state-owned enterprises. The reliability is all made with money. The Internet is worse, especially online games. If you have to go down every three days, you will have to line up at the bank to file a lawsuit.

In addition, it is said that the bank’s data is backed up in three places. It is three computer rooms and they are separated into two places. Now think about how stable your so-called master-slave mysql can achieve

Innodb log-bin recovery