Man, the level of overreaction on this forum lately is truly epic. Hyperbole is the new understated.
Look, we knew when we draftedhim that he has elite athleticism but is underweight and rehabbing a busted shoulder. He is a 34 OLB, and he needs to bulk up for that. Converting him to a true 43 DE was always going to be a multi-year conversion. Why risk that shoulder putting him in there to get blown away by road grading 300 pounders? So we can have an unsealed edge every run play?
If you could draft a Can Wake, JPP, Aldon Smith caliber talent and were told it would take a couple of years for him to adjust ... wouldn't you take that pick? All indicators seem still on course for him to get there. Don't rethink the plan now.
If you want to point to fail picks, look at guys like Dallas Thomas or Phillip Merling, not Dion Jordan. He is actually making an impact despite not having a second move, despite limited playing time, despite being undersized, and despite being injured. The guy is clearly going to be good.