I know Brady has accepted things salary wise to accomodate having better players in the past. And you can say that it was beneficial for him. 3 more Super Bowls.
I just think at some point regardless of how good of shape he is in physically, he is increasingly limited by his age. A split second here with a pass, a split second dodging a lineman or blitz. He doesn’t have to get hurt or anything, it just comes down to the lines are that fine in the NFL.
Yes, other players in other sports have done the same - forego some salary to keep some good players together.
Age is definitely a factor, as is understanding the opposition; he may have just played so long he can be countered with good coaching. That is primarily how the Giants beat the Patriots twice; they reduced Tom Brady to a very average quarterback. He himself complained about the Giants defense; they had his number (both times), and kept the score low.