No, I don’t think that’s true. I don’t think he always would’ve made such a terrible decision. I think things can change over time. He did make mistakes in the past (Welker and Seymour), but this is the first one that cost the Patriots a Super Bowl.
We don't know why he benched Butler or if benching him cost the Patriots a super bowl. We do know he had a reason.
That decision was a product of BB's coaching style or system. He had a reason to bench Butler. Was it because of his performance in practice, something he said, being late or a combination of things? I don't know. I do know it's how he coaches and it has netted the team 8 trips to the Super Bowl resulting in 5 wins and 3 losses.
It's the same coaching style that chose to trade Collins and Jones, bench Tom Brady, not call a timeout at the end of SB 49, and a slew of other things that have been or could have been clickbait fodder in the past. This was no different.
His coaching style, whether we like all of the decisions or not, has led this team on a ridiculous two decade long run. Those decisions, whether we agree with them or not, set a tone for the entire team and for future players who decided to sign here. That tone, that environment and those decisions are the foundation to why they have won or been to so many big games. It's why veterans who want to win a championship come here.
It's not perfect but it is definitely historically great.
You say, "things can change over time". What changed? They just lost in a Super Bowl. They just made it to their 7th straight AFCCG. That's an insane accomplishment. And yes Tom Brady has "covered up some mistakes" or "carried" the team but BB has covered up or carried as well. It has been the perfect tandem.
If it's true that something has changed or "they hate their coach" or "the cliff" or "BB has lost his locker room" stuff is finally becoming true then it's been a hell of a ride but I think there's still more to come. The players they signed this offseason are coming here knowing BB's reputation and they also know that if they fall in line they'll have a chance at a championship. And I'll bet whatever it was that got Butler benched won't be something those players will do.