Even if Real Madrid can take Mbappe to the team, their condition will not improve much. Because Benzema and Hazard are enough for the Real Madrid forward, they played well throughout the entire season and were less injured. Luka Modrich can also play well throughout the entire season. Real's main weakness this season is their defense. Without the two main defenders, Varane and Ramos at Real Madrid, a much bigger void will be created in the team. It remains to be seen what action Real Madrid will take to fill this gap. However, if Atletico Madrid take Mbappe to the team, I think they will undoubtedly be ahead of Barcelona in winning the title.
Mbappe made a good decision to leave Monaco and joined PSG but if this time, he leaves PSG and participate in Real Madrid, it would be a bad and backward decision. Real Madrid squad is old in average age and their key players who brought 3 Champions League to the club, have been in downside of career.
Mbappe can feel he will be the most important player in Real Madrid but only this won't help him to win titles with the club or for his personal titles. The transfer of Varane to Manchester United only make things worse in Real Madrid.
I totally agree with you. If Mbappe joins Real Madrid, he will be one of Real Madrid's most valuable and important players. But winning the title is not certain. The PSG team is a thousand times better than Real Madrid. The PSG team seems to be much more stable this season. Real Madrid, on the other hand, has been even weaker than the previous season. They lost experienced coaches, lost two experienced defenders. Relying on Modrich and Benzeman alone, winning the title is impossible.