Those clubs they you mentioned above can be called favorite too, because they have all won UCL in thw past and would love to win it again. PSG will be carried away with anxiety and they'll not be able to put in much efforts like they did this season before winning the league. Don't forget that PSG has been fighting tirelessly so see hoa they can win UCL and it cams to pass. I believe another team will fight to win UCL next season
Yes you are right, it will be very difficult for PSG to retain the Champions League title in the upcoming season. Because the other teams will not let them do so. The favorite teams like Barcelona, Liverpool. Arsenal, Manchester City and Real Madrid are preparing themselves for the upcoming season and making themselves stronger. I believe that success makes a person lazy and failure makes a person stronger. So I will rely on the last season's failed teams who are the favorites for the UCL title.