Brady became arguably the greatest QB in history and IMO he was. He was drafted 199th overall as "a lightly regarded coming out of college" with "an unimpressive NFL Scouting Combine report" (https://en.wikipedia.org/wiki/Tom_Brady) in 2000 and initially played behind former Argo QB Michael Bishop. Seven Super Bowl wins contributed to his legend. If anyone is to surpass him over an entire career I think it is most likely Patrick Mahomes II.