I think I answered it but going back to your original question...
It's definitely possible. He won a 7th elsewhere (at age 43), the Patriots had a championship drought in the prime of Brady's career (certainly Bill should have gotten more out of that timeframe and I think other head coaches would have as well), and the Patriots left more championships on the table (2015 and 2017).
Well, he won 7, so 6 doesn't seem implausible had he played for examples Indianapolis or Pittsburgh.
I think Bill had more to do with the first 3 championships than the latter 3, although the defense stifled the Rams offense in SB 53, but the most extraordinary part of that postseason was Brady's three consecutive 3rd-10 conversions in OT of the AFCCG on the road in KC. That's an example of something that couldn't have been duplicated by any other quarterback in the history of the NFL. Along with the 4th quarter of SB 49 and the 28-3 comeback. That innate clutchness, which Brady remarkably had his entire career, was something he would have had anywhere.
Well, that's not entirely truthful. The context of the final season in Cleveland is overplayed to excuse away Bill completely losing his team... they were 2-10 after September (the move was announced in November), they were bad on offense and defense, and they went 4-12 the following season in Baltimore. I call that trending down.
The 11-5 2008 season is the most overrated Belichick "accomplishment" ever. In 2016 they got shutout by Buffalo in Foxboro. After Brady returned, they hung 41 on Buffalo in Orchard Park. Arguably 2016 was Brady greatest season. And I'm not a fan of the 10-7 2021 season because it was actually 10-8 with a 1-4 finish and a humiliating playoff loss to Buffalo. We agree though, Belichick blatantly screwed up the 2022 season, and possibly ruined his franchise quarterback in the process, we'll see on this.
The season has to play out, as you like to point out, but if they finish 3rd in the division at 9-8 and out of the playoffs again, then I think Kraft has to call it a wrap on Belichick. It could be even worse than that, possibly 4th with a healthy Tua in Miami, or better if they sign Hopkins. We'll see but even with a best case scenario I don't see them winning the division which is probably the positioning they would need to win a playoff game.