PSG are already on the edge of the Champions League elimination zone and will face RB Leipzig this weekend, so there is no need to expect much that PSG are still not worthy of advancing further. The Champions League seems too difficult for them.
Above PSG is Real Madrid who also have very little chance because they will face Atalanta. It makes sense why Madrid are considered to have little chance, in terms of performance they still can't promise anything and are now bottom of the standings in 24th position, so the match against Atalanta determines whether Madrid advances to the play-off round or out.
I believe you made a typo, your post says PSG will face RB Leipzig this weekend but RB Leipzig are in the German Bundesliga and PSG are French Ligue 1 and even in the Champions league, PSG is not even going to play Leipzig instead PSG is playing Salzburg and RB Leipzig are playing Aston Villa. Above PSG is Real Madrid who also have very little chance because they will face Atalanta. It makes sense why Madrid are considered to have little chance, in terms of performance they still can't promise anything and are now bottom of the standings in 24th position, so the match against Atalanta determines whether Madrid advances to the play-off round or out.