You are right. PSG has no opponents in Ligue 1 to win the title. Marseille, Lille and Lyon must be strong and well-organized if they want to make Ligue 1 better and more competitive. They have to fight for the title. Ligue 1 teams seem to be fighting for second place in the points table. They gave the first place to PSG without any competition.
In Ligue 1, in fact, the tight competition only occurs in second and lower positions, while position 1 of course from the beginning of the season we can also guess if it will belong to PSG at the end of the season, while now the teams under PSG, I think they are only competing to be able to qualifying for the champions league competition and also europe by getting a strong position in the standings, While to become championship of league 1, of course maybe just a dream that is very difficult to realize for other teams in ligue 1 right now.