I see no reason to call the kid a moron. If he is not being played, it is the coaching staff that is making that decision. From what I can see so far, on this defense, there are multiple players that are not where they should be. I do not care what it is, sports, war, chess, or checkers, if you are moving your players in the wrong way, you are going to lose!
Maybin is 22 years old, most of the players coming out next year will be the same age that he will be. Time to let the kid play, can't stop the run, well then, he should fit in well with the rest of the D. It is called OJT, on the job training, it is a common practice in the business world, and this is after all, a business! Play the kid! In fact play all the kids, Troup, Carrington, Just Do It!