When you react immediately to an emotionally charged event, you ignore the shades of gray and risk creating other problems.
The collateral damage to the game from this is a huge risk. If they do it right, it'll be just fine. That being said, how do you stop coaches with remaining challenges from challenging a relatively normal "let 'em play" play where no real advantage was gained but there technically was "contact"? Why not just focus on flagging contact past 5 yards? I don't want to see some kind of no-hands rule, but it has to be better than a random 5 minute delay.