I think it would be better, from a health point of view, to step out of the game while you are still on top. You only need one injury to be crippled for life and it’s much greater to be crippled when you’re over forty than younger ages.
If he had some other kind of record to shoot, such as a record in passes or whatever other quarterback record that he might be able to obtain, that’s one thing. But if just wants to play until he can’t than he risks being a parody of himself.