Maybe it's time we raised reserve requirements above zero.
This is certainly one option, with the virtue of simplicity. I've been digging into the Basel III regs and 2023 stress test scenarios, and I think there are a couple specific weaknesses in the current framework:
1. The LCR is calculated on a net basis, and only applies a 25% haircut to incoming HQLAs. So, assuming neutral cash flow on a monthly basis, LCR only assumes you need to hold 25% of the actual predicted 30-day outflows... at best a week's worth of actual HQLA, and given that there's probably some "lumpiness" in when the inflows arrive, potentially less for some weeks of the month.
2. Fed stress tests are completely asymmetric - they test for interest rates and inflation dropping in a recession, and assume the Fed is loosening MP in response. As far as I can see, there's no testing of the reverse scenario, and that's backed up by the Basel III risk weights actively encouraging holding a ton of US Gov securities & relatively HQ MBS's... which both dropped in value as rates rose.