I understand that, Man United need an adjustment process with Rangnick. I think whoever the coach is they need adaptation. That adaptation has been a long way off and now Man United have played like Rangnick's will. The movement of seizing the ball is very visible, they simultaneously presing on the opposing player. At least a few wins have given Man United the chance to keep going to ucl next season. "I think at the moment Man United is still unstable.
Every coach or player needs time to adapt well. Coaches have to adapt to players while players have to adapt to new strategies, new training portions that may be different from previous coaches, and new rules. Manchester United will not be at his best with Rangnick as he is only given 1 year in his contract. Manchester United will soon find a new coach to replace him. That will prevent Rangnick from working 100% for Manchester United.
Then, what they are trying to do now is to maximize all the potential to get points. It may be difficult, but they are on a good track today. Burnley will be Manchester United's next opponent and they will probably win there easily.