That's not "reality" though. The phenomenon of people "panicking" (ie acting sensibly when their savings are at risk and getting them out while they still can) is a fundamental part of the crisis-process of any bank when it is badly managed.
Saying "well if people just ignored history and group psychology and hope nothing bad will happen and risk all their savings by doing nothing, then nothing bad will happen" just isn't remotely realistic.
Silvergate, SVB and Signature were insolvent. This wasn't a fire sale prompting a decline in their asset values, i.e. classic illiquidity. It was their assets being worth less than their liabilities. If it were purely a liquidity issue, they could have borrowed at the Fed's discount window. (As First Republic appears to be doing.)