"This squad" is not the squad that played under Ole. And just because Ole, who never managed a big side before or after, didn't manage to do it it doesn't mean it's impossible. What is even that logic?
I don't know why you have a such a hard time on the issue of spending. We have a squad that is ill suited to the system Amorim wants to play, we will have to spend more to get the players that we need. Moreover, the even bigger issue is that it extremely unlikely the next manager with play with wingbacks instead of wingers or with multiple 10s or with 3 CBs which will leave the squad more imbalanced than it should be.
I was OK with Amorim coming in and trying something different. It has failed so spectularly so far that it baffles me how can so many not at least have doubts, let alone not be concerned about the implications of continuing with this. But then I remember it is United fans so it makes sense.