I'm actually against that proposal.
It's always been known that if you're caught sneaking in a character that was beyond caps, or are using an illegal tactic and someone presented evidence against you, that you'd risk a banning, even if during the match. Protection against this is not attempting to stretch the rules too far, or break them outright. There's nothing wrong with creativity, but the rules are there for a reason.
That's an official executive decision as well.
Rule violations caught during the match duration will face immediate consequences.
It's always been that way.