Satire about any and all professionals with a special vocabulary has been a staple of fiction and popular ridicule since the 18th century.
Paul FryI do identify the escape hatch through which Foucault eludes the charge that he himself is an author/authority, hence a tyrant. He establishes the category of "founder of discursivity" for the authors he likes. Slippery, perhaps, but you can see what he means.
Paul FryCriticism is concerned with evaluation. There may be evaluative principles implicit in this or that form of theory, but theory in and of itself is not prescriptive.
Paul Fry