Sorry, what do you mean?
Basically, the historical origins of different bank regulations are quite complicated and also differ from place to place, and they were often put in place by (political) coalitions of people who already had not one single motivation but a whole spectrum of them.
And then in addition to historical reasons, you also need to ask why things are still in place. Inertia is one answer, but it's not the only one.
To understand the regulatory framework for banks, the best place to start is the BIS and Basel III. https://www.bis.org/committees/bcbs/standards Generally speaking, international banks follow Basel III in addition to their domestic regulators’ capital requirements (which are probably also derived from Basel III, but have differences just to make things tedious).
However, BIS and Basel III (and the previous Basels) are just what's currently in force for most of the world. I suspect most people would be better served by more of an historical overview. But it also depends on what one is interested in.
Sorry, what do you mean?
-- think that's referring to bank deposit insurance schemes...
US banks tend to meet AT1 requirements by issuing preferred shares.
Binance's approach seems to be based on vibes and a vague promise