Yes, as we are talking about this season, the one that dominates the top of the French League is PSG. There is no other team that can beat PSG at the top of the French League standings, even though they are at the bottom followed by Monaco and Marseille, they also cannot catch up with the points that PSG has collected. There is high hope that PSG will to become champion in the French League at the end of the season.
I agree with you that only the French League and Domestic League can be achieved by PSG, whereas in the European League it seems to be a burden with big teams from all leagues so PSG's steps to qualify for the next round I doubt it.
In the Champions League, it is still appropriate to doubt PSG this season because PSG's performance there is still far from satisfactory. But in Ligue 1, it is quite clear that PSG is still very strong compared to other candidates, only a team as big as PSG should be able to get something more because trophies like Ligue 1 are very common for them every season. So PSG must be able to improve themselves outside Ligue 1 so that the team is not underestimated by rivals from other Leagues when playing in competitions like the Champions League.
I agree, they may literally stay out of top 24 this season and that would be totally shocking and maybe they could even fire Louis Enrique on the spot when that happens. Like the moment it's guaranteed that they are out of top 24, they may fire him on the spot.
Who will replace him could be discussed later on, like they could find some interim manager for the time being at that moment, but the reality is that they should fire him at that moment. This is PSG, they are doing better at league than all French teams in UCL, but in UCL all French teams are doing better than them, Brest and Lille are not teams you should be worried about at all, and yet they are doing better at UCL than PSG, so it's clear that PSG is specially bad at UCL this season and we have absolutely no clue why.
I hope that they get better and get the results they want in the last two games, but it is going to be very tough, I am not expecting simple solutions at all, definitely a tough one.