For this reason alone, Ancelotti may be reluctant to include Mbappe in the squad. Mbappe is capable of scoring a lot of goals and his fitness is very good. But his behavior is completely different from Real Madrid players. Real Madrid is a strong team as a team. Real Madrid's good results are due to the contribution of almost every player in the team. Ancelotti will certainly not want to rely solely on Mbappe to shape his strategy. Mbappe's main problem is his unwillingness to assist. He just wants to score.
Yes, I agree with your view about Mbappe, who looks a little more selfish than his team-mates. If Madrid do sign him Ancelotti will surely change a few things in Mbappe's attitude, and certainly no player is bigger than the club. I think Ancelotti understands Mbappe's attitude very well and I'm sure he can handle it easily, considering that he has coached so many football stars.
If Mbappe doesn't join this season, Madrid will also have no shortage of options for their striker position, and there are plenty of other best striker options they can get in this transfer window. Harry Kane and Osimhen are the two names most talked about in the transfer market this time, both of which are also reported to be in demand by Madrid. But I don't know what is clear that Madrid will remain as a club that has history before Mbappe came, hopefully if he officially joins he can add titles to Madrid.
I doubt that you can create a significant change in Mbappe regarding his self-perception, his character and how he behaves towards other people and teammates. He isn't a gentleman and he has no issues showing his egoistic attitude. It's remarkable how different two world stars can be when you compare Haaland to Mbappe. Haaland is a modest guy, permanently trying to contribute in any way possible, enjoying goals of his teammates, trying to assist them as much and as good as he can while Mbappe is more the Ronaldo guy. I prefer people like Haaland who know that they are the best, but they mean it seriously when they talk about potential self-improvements and also about their weaknesses. This sets real stars apart from others.