Utd were dire throughout, Mourinho is dire. Mourinho doesn't seem to understand that the team needs offensive cohesion and that pushing them deeper doesn't help. When you teach players that to get a result they have to drop into a back 5-6 and park the bus that is how they will play in other games too. When you train a certain way and tell them this way is the way forward, the team adapts to that. If you teach them to defend with 6-7 players, don't expect them to defend well with a few players less in the next game.
How often were Rashford and Lingard all the way back with Blind and Valencia even narrower than them? How is the attacking midfield or striker going to work with zero wide players and half the offence too deep?
Said it before he joined, when he joined and now, they needed to pick a manager to build on LVG's defence and bring a fluid attacking style to the offence/team. Instead they brought in a guy who has made a living using the best squad in a given league already with a cracking offence, made the team more defensive which in the short term solidified them but the only slightly longer term made them too defensive and broke the offence. Starting with that Utd side and with a guy who already put the defensive foundation in but hadn't fixed the offence he was just about the worst possible choice to take over.
Besides his style which is terrible, how Mourinho continues to give the like of Fellaini games I have no clue, drop one useless slow waste of space in midfield but play another one? Where was Shaw, Young(who despite people under rating him is constantly very effective for Utd both defensively and offensively), Bastian and Morgan.
It's actually dumb because both Barca and Bayern made the blueprint for Utd, LVG comes in and fixes some based problems with the club, sorts half the team out, buys/brings through some solid youngsters giving a good base for an attacking manager to come in and bring the attacking flair LVG can't instil in a team... so rather than use the Barca or Bayern blueprint... they went 100% in the wrong direction in terms of follow up manager to LVG.