Been thinking about this some more.
If/when this happens, the banking system will end. People won’t deposit anymore (which won’t hurt the banks much, you are not their main customer you are a product). What will happen though is large firms will start parking capital in something other than a bank.
Those firms are the real customers. Not the average Joe. If say, Apple decided to pull all of its funds and investments out of the US, it would crater the banking industry.
The only wild card is if the large banks cut a deal to protect the large firms.
This is an international thing, it won’t matter in other places as they will be in the same boat. The G20 Summit leaders signed this agreement with major banks....last month in Australia.