You're addressing an issue -- 'booth babes' in 'sexualized' clothing -- different from the article and the comment to which you've replied. They're talking about a more subtle phenomenon, one which the PyCon policy doesn't address (and perhaps is too subtle and subjective to be addressed with any set policy).
But maybe then, this isn't a 'problem' to be 'solved', just a thing that happens and should be understood, and the original article is more an impressionistic lament than call for solving-action.