Virtually all who reach the level of P4 are extremely accomplished. After all, there are only about 65 of those jobs in the world. I believe the difference between how fans define "success" has more to do with on the field talent than anything else that might separate them. I maintain that game day decisions are vastly over rated. Many if not most of the decisions that are criticized by fans are failures do to lack of execution rather than anything else.Weird how so many coaches are making around $10 million a year for a position that is not much of a difference maker. All they do is recruit, hire staff, budget NIL, be a prominent public face of their university, provide general strategic guidance to their coordinators, make key decisions on 4th down go for it/punt/attempt the field goal, provide major input on scheduling and the overall allocation of resources, and decide who starts or sits. You are correct, they are a highly overrated aspect of a football program.
Ryan Day's success has more to do with on the field talent than his coaching genius. Although there is no way to prove my assertion, I believe that a coach like Jeff Brohm would enjoy similar results given the advantages OSU provides its HFC.