The main problem for PSG to not getting good results in the past was mostly because of the unbalanced team they had, PSG had the best forwards however there was a negative atmosphere in the teams but they had the best forwards and they didn't get good results because in the other positions, and especially in the defensive line they didn't have good player, I think this teams still don't have good defender and you can see this problem when they are going to play in the Champions League against strongest teams.
The imbalance of players I think it can still be minimized if they have a good coach but seeing from what PSG has done since a few seasons ago they always bring great players at high prices but it is not accompanied by a qualified coach. Not that some previous coaches were not good like Pochettino or Galtier but if you look at the history and statistics of their coaches they are still below the size of the top coaches and to be at PSG so things like this will bother them because no matter how many star players they bring it will still have an imbalance when the coach cannot manage them well.
We know that currently the strength of the players at PSG and other clubs is quite a big difference in terms of level, experience and the quality of their skills is much better but in the end it will be useless without a coach who can direct them.