a reactionary is one who seeks to defend the system. their reaction is one of picking up arms in the name of capitalism. "left reactionaries," are those who have a veneer of do gooder, but where the rubber meets the road, you see their ideology is just a defense of capitalism. (except with black/gay CEOs for example) so when some 23 year old freshly minted critical theory person comes on the scene and obfuscates class consciousness by directing rage towards selected outgroups, they are in practice, a reactionary leftist. in their mind, they are "on the right side of history," but when you go to the root of their beliefs, they still want to preserve hierarchy, and still enable some rich fucks to control millions of people's lives, because their analysis ends at the thin veneer of "see i said the good thing on social media."