As an academic in the humanities, I’ve always found these comparisons unfair. Of course critical theory is jargon-heavy; it’s a specialized field with a specialized audience who understand the language already. My husband is an engineer. Wouldn’t it be silly if I picked up one of his engineering manuals and called it pretentious because it wasn’t accessible enough to a general readership? Or because it didn’t conform to journalistic writing standards? They’re all completely different modes of discourse with different readers in mind.
And if you have a working knowledge of Butler’s theory of performativity, that passage isn’t particularly difficult to understand at all. It just needed to be broken up into shorter sentences so her train of thought was easier to follow. And that’s more of an editorial issue than just “bad writing.”