I do understand why the NFL wants rules to protect their QBs. If you've got a guy with a $400M contract, you don't want him on the sideline for the rest of the season. (Except for the Browns, for course. Deshaun Watson hurts us less sitting on the bench than out on the field).
However, I'm seeing all these highlight reels with QBs taking off downfield and scoring TDs. That would NOT be happening like that if the defense was permitted to tee off on them just like an RB or WR. You simply can't have it both ways. If you're going to have special rules to protect the QBs, then don't let them take off downfield. Don't know how to implement that. Perhaps you simply state that once you're past the line of scrimmage, you're on your own, and you get what you deserve.