We spent millennia with examples of stable, metal currencies and bank failures. Then, like now, bankers chased risks. First Republic financed long-term Treasuries. Romans financed eastern fineries [1]. Many others blew capital on kings’ failed wars.
Booms and busts are inherent to money and credit, this is a foundational learning every industrialised non-Malthusian society learned fast and, in many cases, including our own, the hard way.
[1] https://epicenter.wcfia.harvard.edu/blog/financial-crisis-th...
https://www.officialdata.org/us/inflation/1800?amount=1#:~:t....
or even in the 18th century:
https://www.in2013dollars.com/UK-inflation
The counter-swings just created an illusion of longterm stability. But it definitely didn't feel that way for people living on the ground (of course a lot of that is down to unstable food supply and not just the monetary system. Not that it was avoidable, you can't really have a fiat currency without a stable and somewhat reliable government anyway).
You wouldn't have had a stable fractional banking system prior to the 1930s anyway. So yeah, in a way you're right.
Generally financial systems are much more stable nowadays than they were under the gold standard.
The printing of unprecedented amounts of money from 2008 to now created those low yields the banks are seeing. And now there was a tiny increase in yields the banks go under.
This would not have happened with a stable supply of the base currency.