I think it has more to do with that Brady was not playing well his last season in NE. Couple that with he was 40 years old as well. Everyone thought Father Time caught up with him and rightfully so. I’m sure Gruden was not cool with giving up a young QB like Carr for an aging, what seemed like a deteriorating Tom Brady. That would’ve been a dumb move. However, Tom’s snake oil personal trainer found him some revolutionary substances that allowed him to cheat Father Time again.