You can say some of his passes looked bad. You can say he's old. But 4600 yards says he can still throw the ball and gash defenses. The offense is going to score. Last year he had a lot of picks but historically he's only about average at 2.5% INT rate.
Maybe he's on the downside or maybe it was just an off year and you get a buy low. In 2018 he was a 4300 yard, 32TD, 12INT, 105 rated QB that won 12 games. An average season for him is something like 4500 yards, 30TD, 14INT, 98 rating. If he reverts to the mean, he'd make us a lot better.
I can't see this happening, but in the least you'd have a legitimate NFL QB that can move the ball and wouldn't be this 190 yards, 15 points a game that keeps wasting a good defense.