I think that's an instructive example of the difference between a stock in the profession of coaching that's worth investing in and someone worth considering to hire as the head football coach at the University of Illinois in two months.
Bill Belichick will go down as one of the greatest football coaches of all time. Does that mean we should have hired him to replace Gary Moeller in 1979 when he was the special teams coach of the NY Giants? Would he have been our Hayden Fry? Bill Parcells recognized future greatness in him at that moment in time, but there's no reason to think he would have been a successful fit leading a Big Ten team then, or frankly even now. He was a failed NFL head coach over a decade on from then, even with Nick Saban as his DC! (and Kirk Ferentz as his OL coach, fun fact).
It's not just catching a bright spark. It's finding the right guy at the right time.
Kellen Moore is not "too risky" or "too outside the box". He's just not qualified for it, and *even if you're right* that he's the next great coach, you'll almost certainly still be wrong. Pete Carroll really was the guy the Jets thought he was when he was given the job as a green, sunny ball of energy in 1994. He just wasn't that guy yet.
Or, Monte Kiffin really was a defensive genius when NC State hired him as head coach in 1980. That just wasn't the context in which he'd reveal what a mastermind he was.