The PSG-Real Madrid match was a total disappointment. I hoped for Real Madrid to revive in the second half but not much thing changed. Xabi Alonso is new there of course and hopefully they will get better in time.
I also did have such a hope but we were all disappointed. But we can still say that Real Madrid was better second half, if not, the score would have been 6 goals to nil. Being able to stop more goals from entering their net and doing lesser number of mistakes was improvement. The most amazing part of the match isn't that PSG won Real Madrid. Rather, Real Madrid played full 90 mins with Vini and Mbappé on the pitch without scoring a goal but conceding 4.Now for the finale I don't think Chelsea have much chance against this kind of a PSG. 
Chelsea also has a young squad but in terms of quality PSG are ahead of them anyway. I doubt Enzo Maresca's players can hold them off in their golden era.
By performance, Chelsea is no match for PSG this season. But statistically, Chelsea is a champion. They won the Conference League while PSG won the champions league, so this is a final of champions. So, anything can happen. Chelsea also has a young squad but in terms of quality PSG are ahead of them anyway. I doubt Enzo Maresca's players can hold them off in their golden era.