In fact, PSG last season had star players in all positions and not just in the attacking position. But yes, it looks like PSG management might think that if they have a squad full of star players it can make it easier for them to win the Champion League title. But unfortunately, it seems like it is a wrong assumption because after all, even though they have a lot of star players but they also need time to build chemistry between players to get better. Moreover, when PSG has many star players but their coach is not used to leading a star squad, so PSG efforts still fail in the Champions League.
You may be right about PSG, I also see that as one of the reasons why PSG failed in the Champions League. PSG obviously have a good chance because they have a lot of star players, but the relationship between the players is not as expected. Messi is very uncomfortable at PSG, that's because he doesn't get as good support as he did when he was with Barcelona.
After all, PSG is not very good at several positions such as midfielder and also defense. PSG need creative midfielders who never give up and are highly experienced in the Champions League competition. While they have some midfielders like Marco Verratti, Vitinha, Fabián Ruiz, Carlos Soler, Danilo Pereira and Renato Sanches, but none of them have ever won the Champions League title in their career. So of course these midfielders don't have the good mentality to win the Champions League title.