Remember that scene at the beginning of It’s a Wonderful Life, where people are all desperately trying to get into the bank because if it fails before they get in, they lose their money? That’s what the FDIC prevents.
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I’m guessing because 1) dumb ideological reasons involving cutting every government service that isn’t the military or immigration enforcement and 2) FDIC is primarily funded by fees from the banks. Consumers are so detached from how stuff works for the most part that removing the FDIC insurance fee wouldn’t give consumers higher interest rates, but just decrease the banks expenses and make them more money.