Club owners don't want any excuses. This is the reason why they give coaches everything they ask including the best players. Coach Carlo Ancelotti wanted Kylian Mbappé and maybe he told the board members that Real Madrid will be unstoppable if the Frenchman is brought to Santiago Bernabéu. I will start judging the player after ten games. The League is still fresh and he has scored some important goals. Mbappe will be successful in Real if there is a good relationship between the players.
In as much as I will agree with you that the club doesn’t want any excuses when it comes to performance I will say it is clear like the Crystal that Mbappe wasn’t Carlo Ancelloti’s requested player but rather it was the club that choose to bring him in themselves. We all know how Florentino Perez has always been a person who adores Marquee signing and in the football world currently only Mbappe has that aura to bring the marketing attention to Real Madrid and that’s why they waited all this years just to get him to sign. One thing about this Madrid is that even if they bring the coaching crew into their decision making process they don’t solely buys what the manager needs but Also looks at other things to see maybe he fit into their plan over the next years and that’s why you hardly see them buy an ex player for the managers or buy just any player they like.
I also agree that Real Madrid will benefit commercially from the signing of Mbappe. Jersey sales, endorsements, media attention, and social media fellowship will increase because of the French star's signing. But I would need to see the source of your information to believe that Carlo Ancelotti was not interested in getting Mbappe. I have briefly checked and found no information about it.
Don't forget that Ancelotti decided not to sign any top striker last season because he was waiting for Mbappe. Rather they decided to buy Joselu as a temporal number nine. Mbappe have always been a fan of Real Madrid and also have a dream to play in the club. Without any evidence to disapprove my stance, I will have to conclude that his transfer was agreement between the club management and the 65 years old Italian.