BS? Shula is no retread like Spags or Fangio; he's young, he's a second-year defensive coordinator who has coaching ties (because the Shula name means as much - if not more - than the McVay name did), he commands leadership, he's already authored excellent defensive performances, etc.
You're right that just because someone is a phenomenal positional coach doesn't make them a HC...but it won't stop them from getting offers if they're good enough - which Shula clearly has been. I've said that I'm shocked he didn't get offers last year, and I'll stick to it. He will get major HC offers this year if he keeps his defense as good as they were today.