When I said 2018 Super Bowl I meant the 2019 Super Bowl from the 2018 season.
It doesn't matter if he has two bad knees, he's the slowest guy on the team with healthy knees. The game has changed. Pat Mahomes won the MVP in a season in which he admitted he didn't know how to read defenses for much of the year. That element of the game isn't as critical as it was. Defenses have learned how to stop it, and you saw Vrabel stop it cold last year...I did too, I was there.
The position of QB is now expected to be a playmaker, to make something of busted plays. To scramble, incorporate RPO elements, throw on the move. In short, in the Brady era, he and Peyton Manning set the bar for what could be done by reading the defense pre-snap, adjusting the plays and route based on that read and executing it with precision. Doesn't work as well now. Defenses have changed. Now the adjustments are often coming post snap. Read what the defense actually does and have the QB and receivers improvise in real time. Brady would be awful at that.