There is no doubt about it, the good thing is that in Madrid there is someone with enough hierarchy like Ancelotti who has made himself a Liga player and the UCL player, Something he was looking to consolidate, for me this year has been wonderful for Madrid, also apart from the personal situation of Mbappé I can't deny that he is a good player, that Ancolotti can easily use him as the only striker that Rodrygo, Bellingham and Vinicius can help him, he really will be very good , it's a shame that such a fundamental piece as Kross has left, if he had at least stayed for one more year it would have been perfect, but oh well , now the Question is to find a good Midfielder who can do Things well.
You are right, Mbappe can get a better ball supply than when he played at Paris Saint Germain. Real Madrid's midfield is filled with players who can supply the ball very well, on the left and right sides they also have players who can send the ball and even penetrate into the opponent's defense area. This is an advantage for Mbappe, so he may not need to work hard because he can be a pure striker who only moves in the penalty box.
At Paris Saint Germain I saw him playing more flexibly, actually that's not a problem and in fact it's good. But again, of course they will follow the instructions of the strategy that will be implemented by the coach. We haven't been able to see what Ancelotti's gameplay will be like after he gets Mbappe. The team is even more complete now that they have the forward line they didn't have this season, and that makes them look even stronger.
If this is about goal contribution, then I would have to say that while Real Madrid have a lot better players than PSG, which means that they will be capable of supporting Mbappe getting better results, it could also be a reason why Mbappe gets the ball less too. I mean there are many great players there, so it means that other players may pass to each other at times and score goals meaning the usage rate of Mbappe may drop, not impossible.
At PSG he was the only one that was the super star, which is why I think it is quite clear that we are going to end up with something quite well for him, he got the ball all the time because he was "the" star there. At Real Madrid many players could play differently and could get the ball instead.