This argument doesn’t hold up, most of Duff’s draft picks arent in the league anymore if they aren’t on the Jets. If they weren’t excrement picks they would have jobs on another team.
That's a bit simplistic and overlooks a couple of major points. The first year or two of most players in the NFL is when they learn to be an effective NFL player, if they're badly coached at that stage then they probably won't amount to anything later. There's the odd guy who figures it out later, but that's usually a high pick who gets a new coach.
Once we've had them a couple of years and then cut them, they're damaged goods. They've become a reclamation project and the new coach has to really believe in their underlying talent to do that, if they even get a second chance with a different team.
I'm not saying that Macc made great picks, just that the coaching staff certainly didn't do him or his players any favours.