Before starting work on Manchester United. Nistelrooy was working for PSV and maybe this means Nistelrooy is experienced enough to help Manchester United where he played therefor years. Even he had a good performance as the coach of Macnshter United when they were playing against Newcastle United and maybe that's a good sign to say Nistelrooy could help this team even more than Ten Hag
I think since Nistelrooy is familiar with the team the best they can do is to keep Nistelrooy for a longer time to help Amorim if Amorim agrees. Because Amorim is not familiar with the Premier League at all.
Keeping Ruud Van Nistelrooy will not be the best option for Manchester United at this moment since they couldn’t be patient for him to complete the season as a caretaker before they can decide weather to sign another coach or not, they could have given him some time so that they can judge from his performance.
For me, he is better than Ten Hag, his pattern play coaching is good, he is doing the right thing, and in terms of substitutions, he is also good because he knows the player to bring in to change the game.
Amorim will come with his coaching staff, he will not have space for Van Nistelrooy that’s why the management let him go, but no matter how good Amorim is as a coach, he will have to struggle to adapt to the Premier League style of play, but if he can work with Nistelrooy, it will be easier because he already knows how the Premier League works.