And comparing a club based on each group isn't accurate to determine the outcome.
In group F which is Real Madrid's opponents, there's Leipzig was at 4th position on Germany Bundesliga, Shakhtar was a champion on Ukraine League, and Celtic was a champion on Scotland League.
While in group H, there's Benfica was at 3rd position on Portugal League, Juventus was at 4th position on Serie A, and Maccabi Haifa was a champion on Israel League.
As we can see there's huge difference where Real Madrid's group have 4 strong clubs inside, while PSG doesn't.
So to say PSG are stronger seems wrong. If PSG are good, he's not in second place at the end of the group stage. They should be able to end up in number one like Madrid so the possibility of meeting in the first knockout phase.
But to say PSG is weak is also wrong. I think if they're right to meet in the first phase it's very interesting. It could be that it was a semi-final too early. Remember last season Madrid also struggled while playing in France, lucky Madrid were able to reverse the result at the Bernabeu.