Again, as my comment [1] mentioned, there are no hard limits. For FDIC to fail, the US government and it's largest member banks (including those considered globally systemic) would have to fail. There will be losses, but there will be no systemic failure. Properly titling and distributing deposits ensures you've met your obligation to meet deposit insurance requirements (although it might not matter such that happened with SVB depositors). You cannot control the regulatory mechanisms, but you can take somewhat straightforward, prudent measures to keep the paperwork you'll have to do and any interruptions to your finances to a minimum.

If your risk model is the US government allowing FDIC to fail, we're well outside of reasonable discourse. Your currency would be food, fuel, and firearms.

[1] https://news.ycombinator.com/item?id=39441532