I agree with your opinion that Ligue 1 is one of the weakest leagues among the top European leagues. In fact, we can see how dominant PSG is in Ligue 1 and how other teams are unable to compete with them. This is different from other top leagues such as La Liga, Premier League, Serie A or even the Bundesliga which have rivalries in competition. But I think PSG is not a weak team when compared to teams from other leagues. PSG dominates Ligue 1 because other teams are weaker than them, but I see PSG can also become one of the best teams in European competition. PSG made it to the semifinals in the UCL and that shows their level. It's just that they have never been among the favorites to win the UCL in my opinion.
You say this because in Ligue 1 there is a dominant team with which it is very difficult to compete and other teams look weaker against its background, recently Bayern also dominated other teams very significantly, but this cannot be a determining factor in the strength of the championship. For me, Monaco is very similar in its politics to Dortmund, France also has good teams and by the way, I don’t watch Bundesliga matches much more often than Ligue 1 matches.