Spending money on a team doesn't equal to winning a title, that's not how it works. If you are in a league like France, then yeah it may work because PSG is the only one who can spend as much money as PSG does, and there is no opponent ,but this year even Brighton spent more than United, so its clear that spending money isn't a win at premier league.

Newcastle is owned by the richest person in the world, spending a billion dollars for the team wouldn't even be noticed on his bank account, and yet they are still being careful because they know that if they just spend the money nilly willy, then they are not going to get anything good anyways. Sure City spent a lot too, but not as much as United, and they are doing much better, so it proves that money means something but its not the full thing and we should be considering how to get better result with time and grow the team. United spent a lot, but they got terrible players who worth much less now, they are spending a lot because they are overpaying the players.