He wants to stay until his contract expires in 2024. This is a win win solution I think, apart from Ancelotti himself this is a good thing for Real Madrid.
Ancelotti is aware that if he leaves Madrid at this time then indeed he will also be quite hated especially in the approaching time for the new season, obviously Madrid will be struggling to find a new coach so he decided to leave after his contract actually ended.
Now he must enjoy his last season in Madrid and must make a difference at least to give the best impression and experience for him in Madrid before he really leaves.
With that kind of money, Madrid can actually afford 4 or 5 other players. But PSG's release clause may have been made that way. In the end it was like ridiculous. Remember Real Madrid have had the experience of failed transfers, I'm afraid it could happen if Real Madrid buy Mbappe. Maybe if Madrid didn't want to buy, or other clubs didn't want him it could have come down in price. I prefer players who like to work hard than big players who are weak because they are too comfortable with money.
AakZaki, Mbappe will not fail like some of Real Madrid's previous expensive transfers. Kylian Mbappe can have a tremendous impact on Real Madrid's performances and he deserves his current value, so I don't think he will ever be the same as Real Madrid signing Eden Hazard from Chelsea.
I believe Kylian Mbappe can adapt quickly to Real Madrid. This team is good for him and it will support his big quest to become the best player in the world in the future. If Real Madrid don't prioritize his signing then they might miss their chance to get him.