He has a good head on his shoulders. He knows he's not going to usurp Jayden Daniels, and can simply bide his time as a backup.
Washington wouldn't have given him this deal if they didn't think he could stick around.
Even if the NFL doesn't work out for him as a player, he would still have any number of options to strike it decently in life, whether it be as a coach, returning to ND for his advanced degree, etc.