Is the contradiction being people associate it with length and not quality?
Anyway, it does matter.
Kestrel said
As a GM you're free to add rules and expectations to your games at pretty much your own wims, as long as it doesn't go below section-standards, which are all more than reasonable.
Sorry for requoting again but as you've said, GM's can add expectations and rules. When 'high casual' is indicated, its put there as a sort of expectation the GM has requested from the interested people. Although to varying degrees (seeing how some people abuse it), it is still a filter nonetheless.
Is it being overused as of late? Yes.
Does it still filter out people? Yes but to a lesser degree.