To my own opinion I think they have to give him time to prove himself, he took over when the team is already in big mess and have no much time but he managed to get to the Europa League final even though he lost he was kind of superb in that league with some incredible winnings so I think they should let him have his way first for at least one season
Manchester United were already in a big mess before Amorim joined the team, but Manchester United performance got worst after Amorim joined Manchester United, a team like Manchester United ended the season at 15th position, it doesn’t make any sense to me, you said Manchester United played well in the Europa league, but at the end the end they couldn’t win the trophy, and they played against Tottenham, a team that their performance wasn’t so good also.
The transfer window is open right now, and Amorim is having the opportunity to sign some players, if Manchester United performs doesn’t improve by next season, then I won’t say Amorim is a good coach for Manchester United. He should sell the players that he won’t be making use of, and he should sign players which he knows will improve Manchester United’s performance.