I don't want to see Real Madrid's performance decline after Mbappe is in the squad, of course I hope for a better performance compared to the previous season. Mbappe is a free purchase which is expected to make Real Madrid even more feared in the world as a team, so it is hoped that all players can make a good contribution and work together throughout next season.
As long as Mbappe doesn't have the same behavior as he did at PSG then I think everything will go well and even Madrid will get better and I'm sure of that. Indeed, we know that Mbappe still has a selfish nature in him and that is a normal thing because he is a talented player and his age is still very young so it will be very difficult to control but on the other hand I am quite sure Ancelotti can suppress Mbappe's ego while in Madrid.
We know that Madrid have a lot of young and talented players but from season to season we can see the level of their ego is not big because they can always be controlled well by Ancelotti including for new players like Jude who came last season he can also adapt well in the end. This may happen to Mbappe because he must realize that this is Real Madrid not PSG when he is acting up then Perez can make him leave at any time.