A good story to tell here is the total bank strike in Ireland that lasted a year, where everything operated just fine without the banks.
So... like Silicon Valley then?
(I guess we're both getting downvoted today huh)
... and personal loans, commercial loans, transactions and transfers, overdraft agreements, insurance brokerage, underwriting, and reinsurance.
Ireland was poor and undeveloped economy during 1966–76 bank strikes. Irish pound had one-to-one link to pound sterling, so Ireland didn't even have monetary policy. Companies were able to operate with their accounts in UK banks. Today it would be total chaos.
For personal use, mortgages is the only normally needed product. Non-mortgage personal loans and overdraft agreements are not necessities (and seems to invite poor financial management).
The rest are insurance products, which are also on the nice-to-have list.
However, loans and insurance are a tiny fraction of what the financial sector does. The vast majority of other products would go mostly unnoticed if gone.
> Today it would be total chaos.
Briefly, yes. Some things without real value would collapse. But I strongly believe that it would stabilize within the first year.
Always measure their utility Vs how well they serve everything outside of finance.