I used to think Manchester United signed wrong players in the past, and that is why Manchester United couldn't improve their performance, but after Manchester United sold some of the players who they thought weren't good enough to play for Manchester United to other clubs, those players performed well at their new club, and a player like Scott McTominay helped Napoli to win the Scudetto. That is when I knew Manchester United's poor performance was an internal problem, and Manchester United players aren't 100% responsible for Manchester United's poor performance. If Manchester United wants a total change at Manchester United, they should improve the things Cristiano Ronaldo pointed out were the problem why Manchester United is finding it difficult to challenge for the Premier League title.
Manchester united is facing some issues regarding their performance from some time. As the thing is already discussed that the reason for their poor performance was they sold some of their good players and the new addition was also not so perfect that's why they decreased their performance. But i think we can't say that only players are responsible for the bad performance. The inner problems also had much impact on the team's performance. Because the players Manchester united sold they perform too well in other clubs so this thought is clear that the players were not wrong. Manchester united also changed their coach to improve their performance . Because a healthy portion of the team's success depends on the coach's abilities.