psg are doing quite well, and are currently performing excellent against all the world teams. this streak will be broken sooner or later, because either the team will be out of form and complacent, or they will face a team that can beat them. it is difficult for them to face a team that is superior in terms of squad quality, so i think the most likely reason for this streak to be broken will be complacency or losing games with a few simple mistakes.
in the final i don't think chelsea are the team to break this streak. i think they are an easy opponent for psg, i think they will win the trophy with a comfortable win in 90 minutes.
They're the best team in the work currently and any team that crosses their path would be dealt with, what's getting me surprised is how they lost by a goal to Botafogo but thrashed other bigger teams that crossed their path afterwards, maybe they allowed Botafogo to win so other clubs would feel they're weak, then take them by suprise. Another suprising thing is how Enrique underperformed when he coached the Spanish national team but went to PSG to do wonders. I just feel pity for Chelsea since they're likely the next in line to get humiliated. Well let's see if Chelsea would break streaks