It is surely a good idea to move to Real Madrid because he will play with Ancelotti who is a much better coach than PSG coach right now. He also will play with quality midfielders and wingers with a winning mentality, and they will respect & support Mbappe as well. It is very different in PSG, he lost respect among the players there. And he seems no longer feels confident and less motivation to play with PSG players. With this situation, the best solution is to leave the club.
After facing problem with PSG and Mbappe have announced to leave club in next window transfer but still not respond yet from Real Madrid and Ancelotti want to sign in, need to memorize last years when Mbappe almost over contract with PSG and Real Madrid try to give offer and want to sign in Mbappe but not reach agreement deal and keep extended contract with PSG until 2025. Seems Mbappe not happy with PSG right now and many time he faces problem with Neymar and Lionel Messi in the field, actually he loss confidence and his performance not as good last season trough several games played for PSG in this season.
Problem faced by Mbappe not with coach but also several player seems Lionel Messi and Neymar after several time he said not happy playing with them and want to ask manager release their contract between Neymar and Messi at PSG.