Brandon Staley is Defensive Coordinator

It's a big man's game and he has size that can't be taught whereas what you described is stuff that can be taught/coached up. Not every player comes into the NFL a finished product, especially OL and DL guys.
His size is a negative absolutely NOT a positive. In fact, it's a huge negative. He would be a much better player if he was 6'3-6'5 at the most.

He's 6'7 with high hips. Low man wins and he's never gonna be the low man.