That makes a big difference though. The risk of losing 10-20% (or even of getting back the full 100% but only after a few months) with no reward for the risk taken would be enough to drive depositors away from regional banks and into the mega-banks.

If deposits aren't backstopped quickly, it won't be startups taking the main brunt of this - it will be other regional banks that see bank runs.

This cannot be said enough times. FDIC insurance is only the absolute floor on recovery. SVB depositors might (might!) face a haircut, but it’ll be one worth of the name.