It's obvious that they wouldn't be able to achieve similar performance next year, because Chelsea have shown other clubs PSG flaws. For Chelsea to humiliate PSG in such a shameful way, it means that PSG is no longer the strongest. They can win Ligue 1 as many times as they want but not UCL.
It's difficult for any team to maintain consistency every season in the UCL, unless they have extensive previous experience. PSG might be able to compete at least until the semifinal next season, but they'll be hard pressed to win the title again, as every team in the league is improving their performance by recruiting new players. This presents a major challenge for Enrique, despite the defeat to Chelsea. The coach feels strongly challenged to continue pursuing PSG best history.
Their defeat against Chelsea must have spurred them on. I think they'll make fewer mistakes in the Champions League. Their performance against Real Madrid was superb, and they dominated the game and won. This match demonstrated just how dangerous Paris Saint-Germain is. They're clearly in a position to be one of the best teams in Europe right now. Their loss to Chelsea led to numerous moments where they analyzed and recognized their mistakes. Next year's Champions League is even more important for manager Luis Enrique.
There is no reason to think that PSG has become a weak team just because they lost the Club World Cup final against Chelsea. The way PSG has finished the entire season is the dream of many big clubs throughout the season. Maybe their plan was right in the final match, but they could not perform according to that plan on the field, which is why they lost to Chelsea. However, PSG may have forgotten all this by now and may be working on how they will do better next season. The way they finished the Champions League this season, they may want to start from there next season and try to stay in a good position in the Champions League for another season with a good performance as a team.
However, although the Champions League tournament is a bit easier for PSG this season, the Champions League tournament next season will be much harder for them, but I still think that considering the performance they have performed this season, they will do something good next season as well.