"""The unskilled therefore suffer from illusory superiority, rating their ability as above average, much higher than it actually is, while the highly skilled underrate their own abilities, suffering from illusory inferiority."""

I think if you "master a language", you don't get lumped in with those who know "a little bit". I think you're just talking about arrogant people in general who think that because they know X, they can berate those who don't know X.