This is clearly different in my opinion because Manchester United has been in a slump for quite a long time, since Alex Ferguson left there has been no coach who has been able to replace him or continue Manchester United's performance so that's how it is for now I think, and from what happened in the last few seasons I think Ten Hag has failed to improve Manchester United's performance, he has been given support and also time to process but the success has not come.
There have been quite a lot of changes made by Ten Hag but we can see there is no development in Manchester United's performance, so there is no need to have high expectations for Ten Hag anymore, I think this will never change.
Unfortunately yes, we don't see any progress in Manchester United, nothing has changed in the offseason and they again have a rather weak start. You are possible right regarding the protracted decline from the time of Ferguson, I still want to say that the leadership of Manchester United slopes to delay the dismissal of coaches who had no success for a long time, it was with Solskjær, now the same thing happens with ten Haga. But unfortunately, he does nothing new, he is trying to find young guys who are not yet ready to win the Premier League, it seems to me obvious that the experience of ten Haga is currently not enough to compete with Guardiola.