Manchester United performance against Manchester City wasn't good, both of them play very bad, Manchester United was lucky they got 2 big chance in near end of the match. If not, they would lose against Manchester City.
And since when Manchester United defeated Manchester City the situation have gotten bad and they are find it hard to reawaken there self, and they are both in a bad situation but United still find a way of defeating the city how the dice have turned away from them and people can not stop talking about how they eventually lost to the Manchester United that are struggling.
I'd say Manchester United hasn't changed, they only have few good players like Amad, Mainoo, and Mazraoui, other than that, they're the same.
If Manchester United have improved it would have reflected in other games so to me they don't seems to have improved in anyway. And whould we say that players are the problem, so there next season might be better so let's hope for a better season for them.