For the runner-up position, it may be filled alternately by several teams for each season but if you look at who will come out as the winner of the trophy, PSG is the only team that has a chance. This is why Ligue 1 needs a change because if the challenger team is only able to play and end the season as runner-up then this league will never be as competitive as other leagues that alternately have champion candidates for each season.
This season Marseille has performed more impressively but has still not been able to surpass the capacity of PSG so we can conclude before the season ends that PSG's dominance is still quite difficult to break, let alone talking about the competition for the Ligue 1 title.
In Ligue 1 it has almost always been like that in the last few years because from what has been seen Ligue 1 will be much more boring when it has passed the middle of the season like now where the superior ones like PSG already have a fairly large points gap with their other rivals so that the dominance that continues to be seen is PSG, not the others. I just hope that next season the competition conditions in Ligue 1 will be very different from the current ones because if the competition is only like it is now, everyone will easily guess who will be the champion in Ligue 1 before the season ends.