The manager is not able to bring about very good performance with all the players that are in the current team of Manchester United. The team may have big stars but these stars are not able to do much for the needs of the team, as a result of which it is seen that Manchester United is regularly performing poorly in the English Premier League and other competitions. Of course, changing some players in the team has become a very important issue. If Manchester United starts the new season with the same team like every time, then it will be seen that they are again ending the Premier League and other seasons with failure. If they do not want to change much, then they will still have to change some of their defenders, midfielders and some strikers. Even if they change four to five players, Manchester United's performance will return to good condition.
There is a lot to fix if Manchester United want to perform better next season and I think it has to be overhauled in all lines and even some of the players in the current squad have to be replaced but that is difficult because it is unlikely that Manchester United management will want to spend a lot of money again to do so because in the last few seasons they have done it and failed.
This will be a very difficult job for Amorim and honestly I am very pessimistic that Amorim can make changes especially with the huge pressure from Manchester United fans who expect significant changes, I think it will not happen if the management does not fully support the changes and make the team as desired by Amorim.