Historically in the 20th century, it is not that common for a bank to fail. Since 2008 bank failures have accelerated greatly.

I also could tell a story about people losing access to their money for weeks, waiting on the FDIC, when IndyMac failed at the start of the recession. But it is not my story to tell as it did not affect me, and it was also one of the largest bank failures in US history, at a time when the FDIC was already undergoing stress, so I doubt it was malice.

I just wouldn't count on FDIC insurance to save you in the short-term if shit starts to hit the fan. Have a cash reserve.

Edit: Here's an interesting graph to ponder https://fred.stlouisfed.org/series/BKFTTLA641N

The first major cluster of failures actually preceded a crisis(the S&L crisis) and fell off rapidly after, whereas in 2008 the cluster was timed with the recession and had a longer tail of failures afterwards that continues to this day.