You'd agree with me that it's not the fault of PSG that the other clubs have refused to sit up, rather they prefer to remain in the position they are in as long as when the next season comes they'd qualify for the champions league competition. Chelsea made us understand that PSG can be beaten. Bring their game to them and you'd see a confused club but not many of the other French teams want to take this bold step so when as a formidable side you don't have a competition, you would have no choice but to rule.
Understanding that PSG can be beaten is no new thing because except last season where they got epic in their performance, PSG has not been a great champions league team except that they always have an appearance in the champions league every season. In Ligue 1 other teams have been unable to bring to PSG some sort of challenge where they will be played with their own style and I see that the PSG dominance in the Ligue 1 can be used as advantage by other teams but they probably do not know how to use it.
Your are right, they have not been outstanding in their performance in the champions before except for last season that the did exceedingly great, no team that can not beaten so I wont even argue that, lets not forget that PSG humiliated the likes of Realmdrid and inter Milan also which we never expected to be like that and even though they were to beat the aforementioned teams, the number of goals involved was not what we expected but it happens which is now a past tense, Chelsea the same to them in the club world cup finals which I believe still surprises them till this moment.
The French ligue 1 isn't a competitive one so theres nothing any of those teams can do to PSG because PSG has everything to combat them, as a matter of fact, the French legaue 1 is not even PSG priority because they believe they always get it easily, there major concern even as we speak is to defend the UEFA champions league which they are the current champions but lets see if it will be possible for them.