FDIC wasn’t on the hook for much of the SVB deposits because they were over the insurance limit, until they realized that wealthy people were going to lose money and retroactively decided to pony up.

I can’t remember off the top of my head what the specific series of events was with regards to the almost-losses by SVB going bust.

But one interesting thing that came out of that is banks immediately had the requirements for how much cash they were required to keep liquid increased significantly. The bank I worked at at the time immediately shifted into hard costsaving mode, and ultimately I lost my job with pretty short notice.

Banks have rules for how much of deposits they can invest vs keeping available to withdraw, as well as requirements for how much they must hold in assets compared to the value of their deposits. There’s also strict cybersecurity and workforce training requirements as well for banks, all enforced as requirements to receive FDIC insurance