Sometimes we tend to know more than coaches doing jobs they've become professionals. Erik ten Hag has nothing to do with Manchester United going under, it was due to their terrible performance that they were not able to do better. When Erik ten Hag left, and the slot was open, Ruud van Nistelrooy coached for about 3 seasons, and they never lost a game in that window, Amorim came in and couldn't do the job properly, Manchester United is big club and needs a big mind with a good team, so far this is what they are missing
I also agree, it is not fair to only say ETH is the cause of Manchester United's bankruptcy, he came when the team was already in a bad situation, but he also contributed to the failure. Because for several seasons he was there and there were no results that he could provide. Yes he could get the FA Cup but in my opinion it was nothing more than luck.
Management should be the first to blame, because they are the ones who should know the problem very well and should solve it quickly, but in fact they did not do that.