I would bet real money that a proper survey would show that 95% of Gmail users don't know about that feature, let alone understand how to use it or undo it. No

I would bet real money that a proper survey would show that 95% of Gmail users don't know about that feature, let alone understand how to use it or undo it. Note I am not disagreeing with you, just adding to the point that this was a super-bad idea.