Pogba has been doing a lot of dirty work recently... Go back and rewatch the Burnley and Sheffield United games.. He has been there for defensive headers.. for the 2nd ball..
He has always done that though; I'm not suggesting he does absolutely no defending, but he consistently doesn't track his man, jogs back during opposition attacks, loses the ball in dangerous positions(leading to opposition attacks), and delays on the ball unnecessarily at times. He has done it since day 1, and probably at Juve too, where he would have gotten away with it more. I genuinely see him do these things in maybe 80-90% of the games he plays, aside from the genuinely world class performance he has, where he doesn't put a foot wrong. It's just how he plays football.
The further up the pitch he plays, the more he can get away with it, but when he's playing as a proper midfielder, I just personally think it's not good enough to be making those mistakes and never learning from them. We now have Fernandes, who makes a lot of mistakes as well, so I would personally just prefer someone more consistent, I would happily take Pogba as that person, if he could do it, but I don't think he can. Fred can make 1 of the mistakes Pogba makes while in possession in our half and get crucified, but yet Pogba seemingly has carte blanch to do it, because he scores and average amount of goals from midfield, penalties aside. Before anyone jumps down my throat, I am discounting penalties because most of the midfielders he would be compared to(when it comes to goals) would not take penalties for their teams.