Just from your post, someone can easily tell you are the person who knows nothing about football, and you don't know analysis because if you knew the caliber of players that have played for PSG in the past, you would know that PSG has had a good opportunity to win the UEFA Champions League trophy in the past, but they failed to win it. In the just concluded UEFA Champions League competition, PSG were the underdog, but Luis Enrique deployed good tactics that suited PSG players, and they were able to perform well and win the UEFA Champions League trophy, which so many football fans didn't expect from PSG. PSG winning the UEFA Champions League trophy wasn't because they played in the final for the second time in 6 years, and if you use that to say that is why PSG defeated Inter Milan in the final, that means Inter Milan was in a better position to win the UEFA Champions League trophy because they have played in the UEFA Champions League final 2 times in 3 years, and they failed to beat PSG. PSG was better than Inter Milan in the final, and that is why they were able to beat Inter Milan in the final and not because it is their second time playing in the final.
I don't know about others but imo, PSG was the underdog going into that final. Inter has UCL title and they have the experience and even what it takes to win one. That's why I sided with PSG on that day. It was not only because they beat my team (Liverpool) but I also watch them do the same to Aston Villa and then to Arsenal. If we recall, PSG faced City in league phase and beat them comfortably. PSG beat like 4 English teams and so it was pretty clear to me that they were a better team.
Inter's only saving grace was their 5-man midfield but this PSG midfield showed us that quality >>> quantity.