The silly thing is that even if he disliked the player, if he gave him enough games to get him to sign, then he becomes a very sellable asset rather than letting him walk for free. They needed central midfielders for the past 4 years. Cleverley got injured and Anderson was rubbish anyway, play him even if he is a ****(I've seen absolutely no indication he is), get him to sign a new contract. Let him get a season under his belt so people are interested then sell him for whatever you can get 5mil is still 5mil more than they got, if it was something absurd like a 60mil to Real deal, then they get 60mil.
This is why the whole thing is bizarre, if he was a disruptive influence, play him enough to turn him into an asset they can sell. If he was great, play him and see how great, if he was rubbish then he still should have got a reasonable shot to show this one way or the other. Plenty of other poor players got a chance. I still can't believe based on how Pogba was playing from September through December, that he wasn't looking very good a year earlier.
My guess is Pogba also banged Moyes daughter, with Moyes and Fergie being such good friends, Moyes asked Fergie to not play Pogba either.