I don't think he would have has sustained success. His attitude and style of coaching is more likely to be successful in college than the NFL. Guys with that style(like Tom Coughlin) have a limit on how long the players can stand them. Once the losing starts, all that military dictatorship style coaching starts to wear thin.
Bill hurt his team by years of terrible drafting. Worrying about drafting a QB of the future when you had an MVP/GOAT on the roster. And his numbers were not showing he was going to start playing poo at any point.
Yeah, well Bill built that team. He has carried some sorry ass rosters to deep playoff runs. The difference is that he doesn't have the greatest QB of all time bailing him out with his greatness.
Make no mistake, right now it is looking very much like that ratio is heavily tilted in Brady's favor.