Yes, winning UCL back to back is a very unique and rare thing. Let me put it this way, for the past 30+ years, the only team that won back to back was Real Madrid, who did win 3 times in a row, but that is it, nobody else had 2 titles in a row. When you consider that, do you really think no team was good enough to win? Of course there were teams that were better than others and still lost.
So because we have a historical data that shows that for the past 30+ years only one team did it once, I doubt PSG will be able to replicate that, and most likely it would be like the other 90%+ of the finals where they will not win. Lets see if we are right or not, but it is obvious that we are going to see these things change, and maybe it would make more sense for them to get a better result.
Yes I agree winning Champions League in back to back years is extremely rare with only Real Madrid achieving it in over 30 years which shows this is difficult competition for any team no matter how good they are. And yes exactly PSG has strong team historical data suggests it is highly unlikely they will win again this year as unpredictable nature of knockout games mostly leads to upsets and prevents even best teams from winning consistently.