I disagree with Mbappe being a "problem" as well, it's just a different type of tactic without him, doesn't mean he was bad or a problem for them just means they are playing differently.
Back when they had Mbappe, he was the star and every team focused on him a lot and even PSG tried to pass to him as much as they can, whereas without him the attention is divided to everyone equally and because of that they can play a bit better team ball and do better right now. If the problem was Mbappe then Real Madrid would have been worse too but they are doing fine and he keeps scoring as well.
I think PSG just learned that they are good enough without him as well, they tried uselessly to keep him, would have been better if they could have sold him of course but they are still the best team in France without him. So, they are trying to play all together instead of focusing on a single player, which is why I think they will get an easy title this season.
Previously PSG was very dependent on Mbappe and it was natural to remember the performance and sharpness that Mbappe has had so far, but we no longer see a dependence on one player at PSG this season after they did not get a replacement for Mbappe, but if this season Osimhen they managed to get, wouldn't PSG be very dependent on Osimhen?
I think there's nothing wrong with relying on individual players as long as it doesn't interfere with the cohesiveness and also the stability of the team, because so far we can see how the other teams in Europe have one or two players who are considered quite crucial for them, I think without Mbappe in the squad of course PSG is still quite stable at the moment in the league because after all they have a better squad than the other teams that exist, But is there a guarantee that they can be stable when playing in the Champions League later?
But in my opinion, losing Mbappe will be very visible if they play in the Champions League, because they no longer have players who can be the differentiator and also the opponent's concentration breaker later in a match.