Regarding the record with PSG is bad I think if PSG continues in the current state and they meet again it will not change and the record is even worse because it can not beat PSG at home again, it will happen, Luis Enrique really gets his light back to be able to dominate League 1 this season.
Lets not dismiss them yet. This season is long, so anything may happen. Marseille needs constancy. They must keep grinding, build up points, and capitalize when PSG turns to Europe. This is a marathon, not a sprint. And the Ligue 1 title race might be exciting.
The tight schedule owned by PSG should be well utilized by the current rival teams, considering that the depth of the squad owned by PSG is no longer as capable as the previous season, so it is likely that PSG's concentration will be divided later when they have to play in ligue 1 and also overcome the pressure in the Champions League.