Real Madrid with their financial ability i am sure they can able to buy him from PSG and not impossible for Madrid to make him as saga transfer this January with possibilities as the most of expensive player transfer in the world but there was a bad rumour because PSG president won't let him went to Madrid this because Nasser Al-Khelaifi had bad relationship with Madrid President so he will let Mbappe leave but Madrid is exception club for him and with his current salary i don't think there will be a team who willing to spend a lot of money to buy him unless Madrid especially seems Mbappe is typical player who difficult to control because of his behaviour
PSG have fenced off Mbappe with a new contract that will see the player stay at the Parc des Princes until 2025, PSG also fenced off one of its star players with very special treatment in his new contract. In addition to salaries and bonuses which are certainly very high, Mbappe is also rumored to have an important role as club director.
Real Madrid will certainly find it difficult to hijack Mbappe from PSG, because Mbappe current salary at PSG is worth 4 million pounds per month. If Madrid are able to provide the luxury that Mbappe has at PSG, then Madrid will have no difficulty in bringing Mbappe to the Santiago Bernabeu.
But I don't think that Real Madrid are still interested in Mbappe now, his decision in the last transfer market really disappointed Real Madrid. Also the Real Madrid fans will not allow Mbappe to sign, they will definitely put pressure on Real Madrid. Honestly, I'm worried that the same thing will happen at Real Madrid if Mbappe is part of them. As we know Mbappe's behavior at Paris Saint Germain made many people disappointed in him.
Talking about Madrid, they don't need mbappe because there are a lot of capable strikers there. PSG must think of a strategy on how to make mbappe not selfish, if in the past mbappe had a problem with neymar it was not a problem but now mbappe has a problem with galtier, this is really not an easy thing. Galtier said that the aim of changing/rotation the position of the three strikers at this time is so that PSG does not depend on any one of the three and that is what mbappe does not like.
I agree with you that there are many players who are better than Mbappe, it is better for Real Madrid to look for other players than to sign Mbappe. If they want to, they can actually get very good quality players. They have the capital for it, the achievements they achieve will definitely make the players want to be a part of them. They're a big club so there's no need to go after a Mbappe, anyway I'm not sure they're interested in him right now.