Whit is playing at a very high level. Looks happy. Looks fresh. Looks healthy. Looks dominant. He still seems to love the game and considering the money he's making doing it, unless he gets injured I wouldn't be surprised to see him back for 2021.
Oline is more art and sync than almost anything else in the NFL game. And the longer one plays the position, barring injuries and health, it seems the better they get. Whit doesn't even seem to be working that hard at it.
He, like Brady, might be enjoying challenging the hypothetical "age limit" for players.