How did you manage to get your prediction, PSG was never seen as an underdog to Inter Milan, lets get things straight who did PSG play against during quarter final and semi finals, their opponent was really the best and they thrive through those stages. I agree that PSG based on their current performance are going to find it difficult defending their Champions League title against this big clubs again, each teams are gathering their best squad for next season competitions.
PSG didn't just beat the giant teams, they totally destroyed them. You know they beat Liverpool & Arsenal in the knockout stages & thrashed Inter Milan 5 - 0 in the UCL final, that made this victory a roaring success.
I cant say this dominance is a coincidence at all, rather I wanna call it Luis Enrique's team tactics, his mentality of playing together, & the confidence of his youth, all together has overcome the injuries and pressure.
Most importantly, PSG's players have the foundation for the future, & there is huge potential for improvement for those youngster. Under Luis Enrique's leadership & as a strong team, PSG will remain the clear favourites in UCL next season also