Real Madrid has much better finances and it is possible that Haaland will be their target next season.
Real Madrid to go for Haaland? After signing Mbappe you say? I don't think so honestly.

Because they don't need a player like Haaland anymore after this signing. Mbappe will most probably play in the centre-forward position which means they won't need another star striker. They don't have the same play style of course but Real Madrid would prefer Mbappe to Haaland for sure considering the way they play.

Besides Real Madrid is full of star players. Let's say they signed Haaland as well. Then how will Ancelotti deal with this? There are many great alternatives for the attacking line. He can't just cut any of them easily.
I'm of the same opinion as you do if he's talking about Real Madrid signing of Haaland this very season, despite them having the funds to do so and plus the fact that Mbappé went to Madrid on a free transfer, so no much funds was spent. Possibility of Haaland moving to Real Madrid would be if Madrid has let go some of its front-line players because, as it stands so right now, Madrid has gotten the right frontline players that are capable of destroying any opponent team that they will encounter, be it in the Champions League, The La Liga and other remaining competitions.