a BIG injury late in his career. Brady got the big one out of the way early (2008) when he was 30 and was able to recover and come back. I'm unsure if he would have been able to do so if he sustained that injury in 2018.
Without destroying their achilles(es?) last season I think Cousins and Rodgers would both be playing better right now. If Peyton Manning wouldn't have had to get neck surgery fusing his vertebrae together leading him to have to completely relearn how to grip and throw a football, I bet he would have made it a couple more years at a very high level of play.
Brady's ability to avoid injury is partially luck, but definitely a skill unto itself. Maybe never eating a strawberry in your life was the secret to good QB play after all?