this is going to be a deal where people are going to say any time a fighter takes an opponents lid off, it will be because of this rule. when fighters have been doing that already.
reality is we will never see this penalty called. as a caps fan I can only recall once a situation where fighters took their helmets off and that was the fight that didn't happen between ovechkin and downey
My simple solution: make helmets a two piece system with the current hard shell and soft inner shell, sort of like a rugby helmet. Players can take off the hard shell/visor and still have a soft padded membrane in case you land on your noggin. Saves the hands and maybe some lives, plus you can put advertising on the inner shell!
...as has been the case in the NHL since the beginning of time right up until the Kinder and Gentler Age of Bettman and his ilk.
To be sure, Bettman isn't pushing this agenda because he thinks it is better for the game/going to draw more fans. He is doing it because his "bosses" want him to push it. Primarily because, as you suggest, they want to protect their investment.
I'm not a "defender" of Bettman, but he often shoulders the blame for actions that the league ownership instigated. He's just the convenient scapegoat.
They should grandfather visors, The taking your helmet off during a fight penalty is a good idea. But the starting a fight with visors is a bad idea. If you make visors mandatory why make that a penalty.