If the UCL had been won with Vlahovic or Osimhen, Juventus or Napoli should have won this cup last year. A player and a team do not change from start to finish. Even Messi couldn't make PSG the Champions League champion. So it's not tied to one player. As you said, Luis Enrique needs to make PSG stand out as a team. If he can achieve this, PSG may have a chance.
PSG president, Nasser Al-Khelaifi have the authority to make things right for the club, he's taking crucial actions to upgrade the team. PSG coach, Luis Enrique have the potentials to bring the team back to stand. UCL is a difficult trophy to win, it's clear how these elite clubs win the trophy. PSG are not fit to withstand there elite opponents, rather they should be keen on winning the usual titles. PSG winning the UEFA Champions League is weigh out of the picture because the Parisians are yet to discover their purpose, the team having challenges when it comes to elite competition.
PSG also started to have difficulties in the French league. I think they are in a risky situation in both places this year. League 1 championship is also in a risky situation right now. They must only be dreaming of the UCL cup. If they actually win the UCL this year, I will be as surprised as an average, unambitious team. If Enrique establishes the basics well, PSG can be a completely different company in 2 years. PSG could be a better team as transfers come from the best options in the regions. Consider that they have difficulty even with Prime Messi.