He's just a shite man manager and that was an obvious risk when bringing in a manager with no top level experience.
Handling the egos is part of the gig. And given how uninterested multiple proven top players seemed to have been he was shite at it.
Cavani, Pogba, Shaw, Rashford, Bruno, Varane, Ronaldo have all shown they can be good players. They've all been uninterested and "injured" with the exception of Ronaldo.
The common narrative on this forum is that these players must be shit, but some of their performances in the not so distant past say otherwise...