Most professional sportsmen reach their physical peak before 30. Fact.
Often times we see athletes peak as early as 23 (Tracy McGrady) and 24 (Vince Carter). But the most skillful positions in team sports need more time to improve, get experience and learn to thrive under stress. Quarterback is the best example with so many players peaking at 32-34 (Unitas, Young, Montana, Roethlisberger etc.).
Brady is a freak example because we legitimately have at least 4 uberstrong candidate years and possibly 8 seasons with a good shot. It's even more problematic because individual stats in the NFL aren't really individual. BobDigital mentioned how 2006 Brady was basically as good as 2007 version but without weapons. Yet, we see twice as many TDs, 80 ypg more, vast difference in completion rate, INT rate, passer rating, everywhere.
So 2007 Brady stands tall, but I'm not sure he was at his best then. He had better health and athleticism then now, but should we trade additional 5, 7, 10 years of experience for slightly better arm strength or mobility? Perhaps, but I'm not buying it.
I remember how pretty much every offseason there was an article on Patspulpit outlining how Brady prepares for next campaign, and he always tried to add more versatility to his game, improve pocket presence, scrambling, fast release etc. How much did those exercises influence his later seasons?
What are the gains from healthy knees and more strength?
What are the gains from increased pliability and hundreds of hours worth of experience?
I believe the sweet spot might be somewhere between 2014-16, but I can't claim it's undisputed. There are great arguments for 2006, 07, or those middle years around 2k10.
BUT as much as I like that guy, I don't see him reaching his peak in upcoming years. I believe he'll put up another prime season, very close to his usual self in previous years. But the peak? Sorry folks, but I don't see it.