Yes, Olympique Marseille had a great start in the french ligue 1 last season, and they were consistent in winning their matches, but I didn't see them as people to stop PSG from winning the french ligue 1 title last season because I believe Olympique Marseille would drop points at one point, which will pave the way for PSG to win the french ligue 1 title. Olympique Marseille finished second position in French ligue 1 table, so you are wrong about Olympique Marseille not finishing second position in the french ligue 1 last season.
I agree that Marseille has been consistent awhile now even from last season. But at some point loosing a few games made them lost their chances to PSG but this season I do not know if they will be able to maintain more consistency. This season and be able to do better possibly ahead of PSG this season but if they must, it will require a lot of work because they are not of equal strength with PSG at all and they do not have same team strength or quality.
From the three matches Olympique Marseille played this season, it's obvious that Olympique Marseille doesn't have a good squad depth and they can't compete with PSG for the French ligue 1 title because PSG squad is far better than Olympique Marseille squad. Olympique Marseille should just focus how they can make it to the top four because that could be achievable for Olympique Marseille this season.