I also agree more with what you are saying because it is indeed time for PSG to concentrate on their performance for next season by finding every replacement for players who will and have left PSG at the end of last season. That was the solution at first besides Luis Enrique who also had to be able to train the players better for next season by increasing the team's capabilities so that the team could achieve what it had not achieved during previous seasons.
The new season is counting down to be started and PSG must hurry up with their transfer. They must complete transfers of players who wanted by PSG to improve their squad strength. They should assume they will no longer have Mbappe after this summer and should not let future of Mbappe affects their transfer in this summer.
Their squad are not perfect and still have some weaknesses so they must take this summer transfer to improve it. If they have long term development plan like Manchester City, they can consider to buy some young players and plan to grow those younth players in their academy.
Like Real Madrid bought Vinicius and Rodrygo when those players were very young, and they spent about four seasons to grow up those players. PSG must do the same as this strategy will help them to save transfer cost and have more sustainable growth. They can not rely on money from their owners to buy star players with expensive costs forever.
Despite the fact that Enrique needs to find players for his team, and the players who left PSG are difficult to replace, we are also aware that he is a good coach and knows how to get good results without using too many expensive players, like Mbappe, in his team. I think that Enrique was hoping that Mbappe would stay in PSG for another season, but that is just my opinion.