I'm done with Manchester United this season, they finished.
Organizing a team takes a long time, it takes many seasons. What happened at Manchester United is that each new coach who appeared immediately made many new signings without first going through a season to properly analyze the squad, the league and the opponents. As a consequence of this error, they spent a lot of money on new signings and the team didn't even win the Premier League.
Manchester United have had 11 managers in the last 10 years:
https://www.transfermarkt.com/manchester-united/mitarbeiterhistorie/verein/985 I think the reason why they've had this number of coaches over a decade is because as a big club, they want to start bringing the trophies as they used to do. Right now they want to stay in the Premier league as much as possible and Ruben Amorim isn't doing the job being that a lot of pressure is upon him but there aren't enough resources to give the management what they are looking for.
I also agree with you that they need time to get themselves back in shape but that's the luxury they don't have right now.
As it is, the only trophy Man UTD are good at lifting is the FA CUP and if care's not taken this time around they may not succeed.
The team's morale needs to be boosted because it's as if the players' winning mentality is so down that they easily accept defeat when they are a goal down.