Last extended contract Mbappe will play for PSG until June 2025 and not sure he will play until his contract expiry after frustrating and PSG eliminated from Champion League. Big dreaming from all player how to winning Champion League tittle and Mbappe have completed tittle in his career from FIFA World Cup, Euro until Ligue 1 but he still not get Champion League trophy.
We don't know all details of his contract with PSG but I believe with Mbappe does know that he is wanted by many big clubs and I believe he would ask PSG to add some special conditions in the contract that can help him to leave PSG more easily. He is still young when he completes this contract with PSG, at age of 25 and I think it's possible to see Mbappe completes the contract no matter how PSG performance will be in next 2 seasons.
Mbappe is the most potential and valuable player for PSG, not only with consistency performance but also he still in the young age and have potential with higher transfer fees. But PSG not priority for selling him before contract expiry after last season not accepted 200 million euro offering from Real Madrid and believing Mbappe will extended his contract. Not guarantee with Mbappe future extend until his contract expiry because Real Madrid still waiting for him and if this season Madrid win Champion League again I sure Mbappe will leave PSG.
PSG don't want to sell Mbappe because they don't need money from play transfers but do need Champions League and they consider him as a core player for their club to win Champions League. So far the idea to build up PSG around Mbappe, Neymar and Messi failed at least in the latest two seasons. In order to win Champions League, maybe PSG will have to let both Messi and Neymar go, then find other younger players who are good in attacking but can contribute better for proactive defense.
Having three super star attacking players who are all free from proactive defense task is terrible for a squad.