I think Bailly was very good whenever he played, but there were stretches in the season when he didn't play, and Man Utd were just as good defensively. Man Utd's backline changed so much during the season, and they were always relatively solid. I think more had to do with Mourinho's tactics and his organization of their defense than Bailly himself. Pogba has been very important to their build up play, he has been their chief creator of chances, and someone who you can rely on to take the ball and advance it through the lines by using his dribbling and strength. Their midfield IMO has looked much less creative without him.
I completely agree with you about him overcomplicating things and trying to be something he isn't. Correct me if I'm wrong here, you obviously know him more at Juve, but my impression is that this problem has become worse ever since he was given the #10 shirt at Juve. Too many times he loses the ball unnecessarily, by trying to do more than he should. He really needs to iron that out of his game if he's to fulfill his potential.
Mourinho moved him around to be honest. If you remember at the start of the season, he was being played as a DM in a midfield two, as the season progressed he was given more freedom and had the likes of Herrera and Carrick playing behind him. His problem is that it seems he has to play in a very specific position to perform; specifically, as a CM in a 3 man midfield with a DM that covers behind the two CM's. He can't play too close to the goal in the AM positon, nor can he play too deep in the DM position. It creates quite a headache for a manager, but when you pay 100M+ for a player, and that player has the kind of ability Pogba has, I'd say you have to play him in his best position and play to his strengths.
Again, his performances aren't enough for a player of his ability, wages or price tag. But I feel there is a lot of exaggeration about how "poorly" he's played. I'd be very surprised if he wasn't one of the league's best players next season. I hate Mourinho, but he's a world class manager, he's known to extract the best out of his players. I think he will get the best out of Pogba next season.
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