Well, I tell you why the offer was rejected. He was actually getting more money from PSG using Real Madrid's interest in him. It is no secret that PSG actually wants to keep him in the squad. And both of the situations actually favored a lot to him and that's how he got a huge contract from PSG. Of course, now everything is coming back to haunt him. He wanted to go to Real Madrid as a free agent. But of course, PSG is not going to allow that to happen. Just like this says, you place a stupid game you win stupid prizes.
Maybe you are right, but it is possible that what PSG offered at that time was not just money but a promise to make PSG a stronger team in European competition by bringing in several star players, so he believed that PSG would possibly become more competitive in the Champions League so his hope of becoming a Champions League champion came true but failed again, so he has not decided to extend his contract and is considering leaving the club on a free transfer because he understands that PSG will not let him go for only 100 million euros if he is still under contract with PSG, and a transfer value of more than 100 million euros will make it difficult for him to choose the club he wants because not all rich clubs will be happy to spend that amount of money on one player even though being able to make Mbappe a player at their club will bring quite a big change, After all, he is a player who quite consistent even though it has not been proven in leagues other than Ligue 1.