PSG performance in Champions League decreased after the appearance of Messi in Paris, in PSG squad. It can be a coincidence but can be one of actual reasons too. I don't think it is coincidence and Messi is one of their problems. One more star players, less contributions from attacking players to their proactive defense. They have become more vulnerable to counter attacks and in Champions League, it is very deadly weakness.
I also think so, Messi has not made a major contribution to PSG in the UCL, Messi has been at PSG for 2 seasons but there has been no significant PSG performance on the European stage, my assumption is because I see Messi as the best player in the world who should be able to make a difference with the other players on the team but this is not the case.
I think Messi's departure from PSG will not have any effect even if PSG can find a replacement in the same position better yet it is possible for this team to be much better.
I also used to think like this that losing Messi at PSG would not be a problem because as long as he was at PSG he had not made a good contribution, for example qualifying for the UCL final, it would be better if PSG looked for new talented young players rather than looking for players who had seen their performance decline, I believes PSG can become a great club next season if they have young and talented players.
Mbappe should be maintained because he always contributes to PSG compared to Messi, so new players are needed on the front lines to accompany Mbappe because new players will also give PSG another chance to be better in the UCL next season.
The sole purpose of adding Lionel Messi to the PSG team was to do well in the Champions League. But the PSG team's midfielders and defense have been very bad this season. And Lionel Messi has so far failed to adapt himself to the PSG team. And just like the previous season, PSG has been knocked out of the Champions League this time.