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.