Mpabbe is really still very young, and if PSG offer him a contract with even more pay, then this is a great option for him to make a lot of money. The most important thing is not to sign contracts for 10 years, as was recently published in the media, let it be such a contract that could allow him to leave the team if he cannot win the Champions League with PSG. If that's his deepest desire, that he can try to achieve it on another team.
He does not want better offer from PSG or at least it is how he shown and he even reacted very negatively after PSG put him into the transfer market and did not call him for the summer training tournament. With such negative reaction, Mbappe only opens the exit gate in PSG more and now he has another offer, this one is from Saudi.
The offer is he signs a contract with a club there, plays only one season and can move to Real Madrid, only Madrid in the next summer. The salary offer is about $200M for a single season that is good and better than spending time in PSG on bench and we know a next summer will be Euro 2024.
The offer from PSG is too long with 10 years and I am sure Mbappe will not be brave enough to bet his career with PSG in 10 more years. He will not sign that contract with PSG so no more option, he will move this summer or next one.