I don't think the fake slide or fake 'going out of bounds' moves need to be regulated into penalties. Defenders can crush a QB who is in bounds, or who hasn't contacted the ground in a slide, all they want right now, which is fine. They can also just touch the QB down, or non violently push them out of bounds, without drawing unsportsmanlike penalties. Faking going out of bounds has been used for decades, albeit rarely, and defenders who let the QB run right by them are just making bad plays. They can just the same put two hands on the QB and make sure they step out, rather than violently forearm them to the head.
The angst that the article makes about fake slides and fake OOB plays just seems manufactured to me. The rules already cover both scenarios. Players will still run afoul of even the most perfectly worded rules. It's a fast game. Don't need rules slowing it down anymore than they already have.