Yeah we can't judge PSG performance until they're in round of 16.
I'm pretty sure they will keep dominating in farmer league and in group phase, they're likely secure the place to qualify for round of 16. PSG and Real Madrid are different, if PSG qualify for round of 16, I don't think people automatically think they will able to defend the trophy.
Liverpool and Barcelona are still strong, they have a possibility to win.
It is impossible to make a definite prediction about the Champions League. The Champions League is very competitive and unpredictable. We considered Real Madrid and Liverpool to be the favorites for the Champions League title this season. But we did not see a good performance from these teams in the knockout round.
Then we considered Barcelona and Arsenal to be the favorites for the title. But both teams were eliminated in the semi-finals. Unexpectedly, PSG played well in every match of the knockout round and won the Champions League title for the first time.
Next season, Madrid, Barcelona, City, Liverpool, PSG and Arsenal are all trying to increase their strength. Their target is definitely the Champions League title. So it is not possible to make a prediction right now about which team will do well next season.