Well you never can say, it's football and anything can happen I mean there are teams that have done it before so it's very much possible that PSG can replicate their previous success although it's not going to be easy as most of the big teams are well aware of their pattern of play so they will likely more match their energy and make it very difficult for them to win. The Champions League is filled with lots of strong teams and most of them are now equipped with quality players ready to win the league.
PSG doing the same as they did last season in the champions League will be miracle, I know that football can give silly results sometimes but I will want to ask, hope you have watch PSG play at the recent time, no doubt they are big team, do you see them as a team that can defend the title this season, I know that they answer might be we won't know, my own answer is I don't think so, Liverpool is hot in the EPL other teams are still not taking things easy, I even forget to mention Barcelona, even Realmadrid that PSG defeated last season won't want such Mess to repeat itself again, so it might be the same way they did it last season, however it is early to conclude, let's allow event to keep unfolding to see who takes the title this time.
For me, i don't really see PSG getting a back to back Champions League trophy looking how well they have been playing since the cwc final. Although I may change my rating looking at their performance after the international break and maybe how well they perform at the group stage.
I know last season looking at the group stage performance one may not rate them as favourite but I will be sticking with this also.