PSG team could not use a player like Lionel Messi well. One of the reasons for this is that the coach of the team does not have enough knowledge of how to use a player like Lionel Messi.
So far I have never heard anyone say that to PSG except you today, because if you say the team coach cannot use a player like Lionel Messi, it means that other players cannot be used better by a coach. But when there was still Lionel Messi at PSG I think the coach put him in a very suitable position so that PSG can continue to win trophies in Ligue1 even though PSG have never succeeded in the UCL as long as there was Lionel Messi in the squad in the past.
IMO, from my point of view, Galtier is a pretty smart trainer and has a lot of strategy. Unfortunately, he doesn't have the experience to handle a club as big as PSG, let alone one with so many stars. we can see that the previous PSG coach could not control the situation in the locker room, so there was a lot of commotion among the players. Plus, Galtier doesn't have the freedom like other famous coaches to bring in the players he wants. PSG is sharp up front, but weak in midfield. when one of their three star players was injured, it was obvious that their game performance had greatly decreased. The midfielders they have are not very creative when helping build attacks. So, Galtier tends to change his formation patterns.
Now, Neymar, Messi, have left, as has Galtier. PSG is currently being coached by Luis Enrique, it is hoped that he will be able to make PSG much better. unfortunately again they need an experienced midfield figure, especially an attacking midfielder. there is also a target target, namely Bernardo Silva, reluctant to join this squad. which in the end, Enrique must maximize the available players. to build this team much stronger, they need time. well, let's see how far this Spanish coach is able to take his team, especially in the Champions League competition.