Star players alone cannot bring PSG to the highest level of the UCL, Messi, Neymar and Mbappe have their own egos and want to be superior to others so it is not clear why PSG failed at that time. Now PSG management is starting to learn that what they need is not just star players, but a history of struggle. This means that PSG in League 1 is used to lifting trophies, but in the UCL competition it is just an ordinary club because PSG does not have stability. This season there is only Mbappe in the UCL and the results are not too bad, meaning that basically PSG must be able to create a stable squad. Now Mbappe departure will leave a lot of work to do, without a pure striker replacement then I'm not sure next season in the UCL we can go any further.
Have some star players in one team give problem for PSG behind most of the playing with their ego and prefer with individual skill than playing as unity team.
PSG have star players when signing Lionel Messi and trio attacking line Neymar, Mbappe and Lionel Messi failure make PSG reach higher level performance in Champion League and only get dominance by winning domestic league. I think need experienced manager when bringing many star player in one team how to make team playing for team than individual.
For next season, PSG without Kylian Mbappe and seems better for team working without any players has ego, but its bad impact will PSG become more successful after leaving by Mbappe or PSG get top performan in Champion League next season.