Actually in this case by looking at some of the rumors that have occurred, especially with the news about Mbappe extending the contract at PSG for 1 season but with a note that he must be sold next season, PSG is indirectly ready to lose Mbappe but not ready to lose their money and business.
PSG is doing this so that Mbappe can still be sold next season not left free so that they can do business properly with several clubs including Madrid.
PSG are just trying to keep their heads above water with the business and money they will receive from Mbappe's sale for now.
Neymar became an Al-Hilal player, given this news, it was very important for PSG to keep Mbappe in the team, because if he left, PSG would lose all three strikers. To remain in this position at the very beginning of the season is not very good, so they understand the importance of Mbappe for the team at the moment. What happens next will be decided during the season, because Mbappe's contract is valid until the summer of 2024, during which time it is possible to convince Mbappe to extend the contract again.
And Neymar decided to leave for Saudi Arabia, perhaps this is a good decision, after all, 300 million in two years, this is a lot of money.