Dembele is also a great player, although Mbappe is much better known as a world striker. PSG also once had a number of world star players at the club, but they also failed to become champion candidates. Luis Enrique needs to build a better squad and must prioritize collectivity over individual skill and he needs to learn a lot from what Pep Guardiola did at Manchester City because their squad is also not strengthened by world star players.
City is a great club. But this season they seem to be having difficulties when their main players are injured. This can be seen from their last 5 matches when Haaland and Kevin De Bruyne suffered injuries. I'm afraid they won't be able to go further in the champions league this season. And for PSG I agree with what you said that they only have Mbappe as a world class striker although I also don't underestimate Dembele. But the problem at PSG is how Enrique makes collective team play because I see that currently they still only rely on one or two players in their game tactics.
Manchester City's form is worrying me, especially with Haaland and De Bruyne out injured. It's like missing a vital engine part. A top-tier team like City should be able to function without one or two players, but they're suffering. They dominated the UCL group stage, but this slump is worrisome.
I think City set a high bar last season and aren't meeting it now. More than ever, they depend on important players. Without adaptation, their Champions League chances are slim. They must quickly find that winning formula.