I may be wrong but it seemed that the point of the fake article was to critique the poor quality of some academic writing. Butler is not alone in that, she is simply one of the most prominent examples. But it is a problem! Firstly because this material is not only not being robustly criticised, but is actually given merit, and secondly because it devalues what may be valid arguments when made by someone who can write coherently.
Thomas Laqueur, for example, makes a similar argument but does so in clear and concise language. Saying that he doesn't dispute the existence of biological sex or feel the need to use scare quotes around the word 'sex'.
It's not an attack on gender studies, it's an attack on poor quality academic writing, which, unfortunately, is rife within gender studies. I'd dispute the idea that radical feminists are known for being unclear, but even if that was the case, the answer is to improve the quality of radfem writing, not to defend incoherent jargon.