99.9% of the time this is correct. The Patriots were one of the very few times where it did.....until it didn't. Belichick failed to adapt to what a post-Brady free agency landscape would look like, and thought he could still get away with skimping on paying big contracts and finding talent in the later rounds of the draft, not factoring in that having the greatest QB of all time helps cover up a lot of the holes of the whiffed draft picks -- Guy can find defensive studs at any round in the draft but absolutely terrible at finding offensive talent outside of the Tight End position.
He did go 11-5 with Matt Cassell at QB when they were absolutely loaded in 2008. He won 7 games in the covid year, with a new QB who had no offseason with the team in the corpse of Cam Newton. 10-7 with Mac in his rookie year with fucking Jakobi Meyers as their top receiver -- any other coach would've won like 5 games at best with how abysmal their offensive talent has been the last several seasons. Bill the GM has absolutely screwed Bill the Coach, I'll 100% agree on that.
Belichick is a defensive mastermind -- Those first 3 Superbowls, plus the last one against the Rams, were all about the defense moreso than the offense. That Superbowl against the Rams was like a defensive masterpiece; the man shut down one of the most prolific offensives the NFL had ever seen upto that point. As much as people wanna give Brady all the credit, the guy had a top-10 defense in the league for almost the entirety of his career. Not only that, go through the rosters and look at how stacked some of those Patriots teams were, especially the 2007 team -- they were like an All-Madden fantasy roster.
Also, to say Mac Jones outshined Lawrence and Fields is a bit loaded statement -- Lawrence' rookie year was tainted with the abject failure that was Urban Meyer in the NFL, and Fields is pretty much a Bust. Mac had a good rookie year, but pretty much got exposed when both McDaniels left and teams started to get tape on him and realized he couldn't throw more than 20 feet. Mac could absolutely go to a team and recalibrate his career under the right coaching regime, but the guy is straight shellshocked out there on the field presently and is going to need to be reprogrammed to play at the NFL level if he goes to another team, and I can't see anyone bringing him on as a starter presently.