When you watch the tape, play in and play out, opponents really have planned to stay away from Gary.
That, combined with his injury shortened season is what accounts for the lack of numbers.
Also I would add that Gary is still a bit raw in his pass rush technique. He'll gain the edge, and all that is needed is an arm over technique to break clear, but he doesn't have that move in his bag of tricks. Same thing with his under move.
Those things can be coached up.
Gary, if he doesn't go "fragile" on us, is a very talented play who should be a very productive pro.