I don't think it would be so good to blame just one person for this thing that continues to happen to PSG every season. Because PSG, which used to have more stars in their squad, was also unable to win the UCL title, so this is certainly not just one person's fault. But it is more about the pressure of the game which is always easier in its own league, which makes it difficult for PSG to develop when facing elite teams entering the UCL competition. And PSG must be able to fix this as soon as possible before next season starts again.
If that's the problem, why did they have difficulty bringing the Champions League trophy to PSG when there were three star players at PSG in the previous season? Football does not rely on one person, but teamwork is much more needed and the performance of the coach is one of the important factors for success in any competition. So I agree with you that blaming one player is not enough of a reason for PSG to fail in the Champions League because there are indeed many other things that are quite crucial.
I hope Luis Enrique is given the ease of recruiting players as he wants so that he can work well together in integrating the team's strengths. If you look at his abilities, maybe Luis Enrique is the right coach for PSG, it just takes time for him to bring success in the Champions League.
They don't have to blame each other, what they have to do is introspect themselves on why it is so difficult for them to achieve a very prestigious title that they don't currently have. So I also really agree that there is no one to blame, it just seems like scapegoating just one person for their failures so far. Even with the 3 stars they once had, they can't do much, right?
It is their collective duty to find solutions to what they are facing. Because they are a very good team financially, they can have star players. But as you said, football is a team game, so they can't just rely on one person. Maybe the above average abilities possessed by some of these players are a good value for them, but they still need to be better at playing as a team. We can see that a team that is said to not have star players can play very well, yes they can do that because their team play and chemistry are very good too.