I think that's it's a wider issue of finding the right balance between the artistic freedom of creators (let's put aside the whole "is it art or a product, commercial considerations") and, when you don't believe that the free market will just auto-balance everything, the right level of militancy, pressure and coercion to have more diversity in female characters designs.
People are perfectly entitled at making "ideological" or "dogmatic" (in quotes because it is perhaps a pejorative way to put it) criticism about design being sexualized along patriarchal lines. Even "wrong" criticism can be interesting even if built on a faulty premise of arguably looking way too hard into something, if consistent enough.
But yes, the ERA variety doesn't feel very rigorous, honest or accomodating to any flexibility most of the time. The unearned self righteousness is the real killer, it often reads like people more interested in being right than actual discussion, working back from the conclusion.
