I agree with you, they need a total overhauling of players and of the Man united management team as well, they can't be doing the same thing over and over again and be expecting a different in result. In fact it's better they even start from the scratch and offset almost all the their players and retain a little key players if they can get the needed results, and further restructure a whole lot of other things going wrong within team's management board, this way, they will be able to figure out what is really the problem with the team and if it's not gonna help them solving their almost a decade of problem.
There are stages to how a club went from been the best to one of the worst, each club that existed in the 60s and 90s have experience this and only few of them are doing well currently and I think Manchester United is now in that era. For instance, look at Aston Villa, their major trophies were made in under 20 years and since then the club can't repeat that again, that's what Manchester United is experiencing now, just accept it that nothing good will come now until they fix everything.
Many people castigated what Ronaldo said about the status of the club bit what did they said, no player is bigger than a club, they made it a campaign but every since he left, nothing good has came out of that club, it has always been noise and noise. Look at how they lost to Tottenham, game that could have been easy and flawless, they couldn't. My first sign I'm expecting Manchester United to do is to sell Onana, that guy has done enough in my opinion,
Manchester United fans know what a successful team should be like because there was a time when Manchester United was very successful. Now the team is far from that success and the fans are very upset about it.
In order for Manchester United to be successful they need to make big changes because their opponents are very strong and they are getting stronger every season. It is not easy to make big changes to the team and it requires big money. I am not sure that Manchester United has the financial strength to do this for the next season.