Sorry - the logic just doesn't hold.
Look at George Seifert's switch from SF to Carolina.
Look at Kubiak going from Texas to Denver, to the final year without Manning.
Look at Holmgren going from GB to Seattle
Look at Dungy going from TB to Indy. Did he magically overnight learn how to game plan offensively?
How about Caldwell when Manning left, Painter really got coached up.
Whisenhunt with the Cards before/after/with Warner.
Hell, look at Belichick on the Browns and Pats before Brady. You really think Belichick just all of a sudden learned how to coach in 2001? His prior 6 seasons as a head coach he had 1 winning season.
These guys didn't all of a sudden forget/learn how to coach. You are giving far too little credit to the QB running the team.
All that is great but still doesn't fit the bill for what I asked about. What you listed off only enforces my point. Yes, it is easier to win a title or two with a HOF quarterback than not. But all the cases you brought up did not lead to 9 Super Bowl appearances for other elite QBs. The logic being that an elite QB trumps all coaching.
No one is saying that the Patriots would have been better off without Brady. It's nearly impossible to discuss Brady without BB. The question I am raising is if other elite QBs have won titles, how come guys like Peyton (2), Brees (1), Roethlisberger (2), Warner (1), etc. haven't won 4-6 of them? Is Brady himself the sole or main difference in having so many more titles? Or is it Belichick?
Like I mentioned earlier. Brady doesn't play defense. There have been 53 SB winning teams. The defenses in those teams ranked in points allowed in the regular season:
Top 1 - 15 times (28.3%)
Top 5 - 33 times (62.3%)
Top 10 - 45 times (84.9%)
Sure, once in a while a team and defense gets hot at the end of the season (01 or 11 Giants, 06 Colts, etc.), but their defenses showed up in the playoffs. The point being, the saying defense wins championships did come out of thin air.
In the 6 times the Patriots won the Super Bowl, those defenses ranked 7, 1, 8, 2, 1, and 6 in points allowed. Since 2001, the Patriots have ranked in the Top 10 in points allowed every year except 2002, 2005, and 2011. Guess what? If those other quarterbacks had defenses like the Patriots did, they very likely would have won more rings too. Belichick has produced Top 10 defenses 25 times over his career.
Seifert had 0 Top 10 defenses when he coached in CAR. Kubiak had 2 Top 10 defenses in HOU. Holmgren had only 3 seasons with a Top 10 defense in SEA and went to the SB in one of them. Dungy had one of the other blue chip QBs of this generation in Manning . . . yet still could only win one SB and with multiple years of so so defenses. Even in the years they HAD better defenses, they still didn't win.
You brought up 2001. Brady averaged 190 yards with 18 TD and 12 INT that year. Was that so outer worldly . . . or maybe it was the defense that more carried the team? Ditto for 2003 and 2004. Brady did not rank very high in most passing categories in either of those years . . . he was Top 10 in TD passes, but he was not the main reason they were winning (averaging 230 passing yards a game or so). The defense those years was outstanding.
Bottom line, the Patriots don't win their first 3 titles without a stellar defense. Brady had nothing to do with the defense being phenomenal. We can't tell what would have happened with a different QB as that's not how it played out, but the question has been raised many times how those teams would have fared with one of the other preeminent quarterbacks in the league.
In their more recent SB runs, Brady certainly has saved them and led come from behind victories in the post season.But it works the other way as well. NE scored 14 points against the Giants (and lost), 17 points against the Giants (and lost), and 13 points against the Rams (and won). If the Pats defense didn't show up to the extent it did this past weekend against the Rams, all the talk would be about how Brady could only get in the end zone one time. NE also lost when they only scored 13 against the Broncos in 2005, 14 against the Ravens in 2009, 13 against the Ravens in 2012, 16 against the Broncos in 2013, and 18 against the Broncos in 2015.
Brady and all his GOATness has failed to score 20 points 10 times in the playoffs on teams that scored a million points in the regular season. The defense bailed him out in 3 of those games. Ten games represents 25% of his post season starts. That's almost double the rate of games under 20 points compared to NE in the regular seasons. So sure, let's give Brady all the praise in the world when the team wins in the post season but not give him much blame when the team can't score and they lose.
The way things have typically worked out for NE is that they win when the defense plays well consistently and the offense does enough for them to win.Other than the Eagles game, NE pretty much scored less in the SB than they did in the regular season. Maybe that's the game planning and play calling, but several times Brady did not lead the Patriots to score a lot of points.