Talent can be found anywhere, no doubt, but he isn't all that crazy for wanting talent from a conference known for churning out NFL quality and damn near keeping up with the rest of the country combined.
Not an exact science of course, I certainly wouldn't advocate drafting only SEC players for an entire draft, but some of the logic works.
5 star type recruit goes to Bama. Elite coach. Faces other elite talent in practice everyday, faces other elite talent each week, does this for 3-4 years.
Could Wentz make that same claim? Not even close.
Does that mean every SEC QB is better than Wentz? No, course not. But might they be a lil more prepared, early? Maybe, I dunno.
I would moreso stretch his belief to say "football factories". Like SEC + USC, Ohio St, Texas, Florida St, Miami etc. Probably half the NFL comes from those ~15 schools. Maybe more.
You'll absolutely find gems from Akron, or Pittsburgh, or Wyoming and what not, but safer bets would be placed on the known entities. Key is, your own coaching. If they can truly coach, then you really can draft anyone from anywhere. If coaching is limited, you really gotta play it safer, imo.