Another thing people can’t comprehend ? That in the FA era, that BB has won six rings. Yes, Brady was a HUGE contributor. But there are plenty of games (including SBs) that were as much about the team around him.
Sure...Belichick has certainly done well. But do you realize how big an advantage he has with Brady plus Brady's top skill players? To put in perspective, look at the other elite quaterbacks around the league. Manning's top WRs were getting $12-14M each and there were two elite ones in Indy and Denver, plus often elite, high-paid RBs. Rodgers always has his $12-14M receiver (or two). Michael Thomas is making over $20M in New Orleans.
The Patriots were paying Gronk $7-9M per year throughout his contract; their WRs, including Edelman, have rarely exceeded $5M.
I have posted a whole bunch of comparisons, but typically the Patriots are spending somewhere in the $35-45M range for QB/WR/WR/TE/RB, while Manning's Colts, Rodgers Packers, and many other elite offenses are spending over $60M. That's a massive difference. And the Patriots have consistently fielded a top offense regardless of whose around Brady.
That's just otherworldly quarterbacking.
Give a bunch of coaches Brady's production by spending that little and they'll be able to fill out their rosters with elite talent and depth as well. And of course, give them the most clutch, never say die machine, who is actually better in the postseason than the regular season with the chips down (no other elite QB is like that.)
Belichick is great. He's going to have to play on the same playing field as other coaches/GMs when Brady's gone. Being great may not be enough to win championships; it often isn't.