He is in poor form at the moment but I still think he has a future here. He is being asked to play a holding role that clearly doesnt suit him - all of his best performances and moments have tended to come further up the pitch. Furthermore he is being asked (especially tonight) to be some sort of deep lying playmaker, since has been on the left and Bruno is practically up front. This was another way in which we missed Maguire.
McTominay does a lot of things well. He can run with the ball, he can tackle and intercept, he can beat the press, he can shoot, he can win headers at both ends, he can shield the ball and be physical. His strengths are clearly not to be a playmaker, nor being really positionally disciplined.
The good thing is that it is easy to imagine what the perfect midfield partner for McTominay would be - basically a young Carrick. Someone who can hold their position and play the longer, more creative passes forward. I am confident that if you put McTominay next to a player of that sort of mould, it would be an excellent and well balanced partnership.