That's not a way to prevent the bank run. That's just choosing to not be a part of it. Unless you can both coordinate with and convince others to do the same, you're not preventing anything.
Imagine the ALL-CAPS tweets and backdoor phone calls that could have been possible if these very same investors (who now rally behind the shuttered and reopened bank) could have called for calmness instead of panic. But that's not what happened. Once the run starts, you can't stop it.