I think there's a real misunderstanding here with the distinction between banks, depositors, and what protections apply to each. The scenario (betting on red) is illegal, but assuming it was not, it doesn't matter to the bank whether or not its depositors have their deposits protected.

I can kind of assume what your misunderstanding is, but it's not completely clear. I think you are assuming that if the deposits are protected, the bank gets to keep the deposits and continue running. This isn't how it works, though. As soon as the bank becomes insolvent (loses its bet on red), the bank is shut down and its shareholders are wiped out. The FDIC sets up a new, government run bank to hold and guarantee the deposits, and then tries to find another bank to sell the failed bank's deposits and loans. Right now there is no Silicon Valley Bank. If you had deposits there, they are now held by Silicon Valley Bridge Bank, N.A, which is a new bank operated by the FDIC.