Paris Saint Germain even took the risk of sending people they did not want in the team to prevent Mbappe from leaving. That's why Mbappe's ego was a little inflated, but the team he came to is Real Madrid. Even Cristiano Ronaldo did not stay in that team. We can say that Mbappe may experience similar situations. Kylian Mbappe is a very good player. He will definitely be useful to Madrid, but he needs to reduce his ego a little.
I think that what worries us most about Mbappé's situation at Madrid is not his performance, because he is a player who does his job very well, in fact he is one of the best, because his speed is very great and he has a lot to solve a complicated match, but the communication and ego part is quite complex because that can affect the whole team in general, because being in a team means being in harmony with everyone so that they understand each other better on the pitch. However, I think that this issue will be handled by Ancelotti, Ancelotti is a coach who gives and imparts a lot of respect , and I think that will be Mbappé's brakes at all times.
Mbappe is certainly aware that at the Santiago Bernabeu he is not the only star in Ancelotti lineup, even before his arrival, Madrid was able to win the Champions League and La Liga trophies. So far Madrid is still very careful about the transition of players within the team, veteran players like Modric will be an example for new recruits like Mbappe. Ancelotti has often handled a number of star players, I think Ancelotti will have no difficulty taming Mbappe ego. Bringing star players together in one team is quite risky, apart from being able to bring in lots of trophies, if it cannot be managed well it can cause a team to experience setbacks.
On the other hand, for his first season Mbappe will try to adapt, build chemistry with other players, and try to understand Ancelotti's wishes well. If Mbappe prioritizes his ego too much at Madrid, thereby potentially destroying the harmony that has been formed, Florentino Perez will not hesitate to let him go in the transfer window. I think Mbappe is now an adult, and he will be more mature when he joins the Madrid players.