Where did i ever say that ?
I'm directly quoting karen7 saying Mbappé has not proven himself because he plays in a not big 4 leagues.
Where do you see i'm inferring anything about the whole league level ?
And if you want my take on Ligue 1 level, i would say it would be pretty good if there was more money in. French clubs are raided by PL clubs usually or even German clubs for their prospects because the financial context is very uncompetitive for french clubs (more taxes, DNCG, etc.)
The problem of Ligue 1 has never been quality per se. Just clubs cant enjoy their quality players long enough.