He literally doesn't care. He was a fax error away from joining Real Madrid when he was at his peak and when United were at our lowest. He's just here for the money, nothing more, nothing less. You can see it in the way he plays and lack of dedication to the cause. The goals conceded against Kluivert and Calvert-Lewin are indefensible, he made such a meek, pathetic attempt to make a challenge that we may as well not had a keeper.
I also don't see how Maguire is more culpable than de Gea. Maguire was beaten for pace by their first goal, but pulled Calvert-Lewin out wide, and he was forced to play a nothing ball into the middle which any keeper should have easily dealt with. Their third goal, both Maguire and McTominay played Everton onside, but de Gea's lack of a challenge on Calvert-Lewin, again, simply indefensible.