>He believes that the insistence on the use of gender-neutral pronouns is rooted in postmodernism, which he sees as thinly disguised Marxism. I've only been studying theory for a few years but how is this interpretation of postmodernism possible? It seems to run counter to one of what I understand to be the foundations of the movement - the rejection of metanarratives.
That being said, many strands of postmodernism in universities have come to teach that there is nothing outside of language itself (that's a common reading of Foucault and Derrida), so everything can be seen as a language or sign system. Want to change "reality" (as if there is such a thing!)? Just change the language.
Another stand holds that there are only two really important groups: the powerful / powerless, which could also be seen as the "oppressors" and "oppressed." Everyone is supposed to be in one of the two groups. This gets grafted onto identity politics in rather unpleasant ways (IMO).
So in the pronoun debate, people who are transgendered or non-gendered are the oppressed and need help; everyone who is not "helping" them is the oppressor and must be opposed.
This, anyway, is the line of thinking, though it isn't my own view of the world. To say that everything is linguistic seems unlikely. When I was in grad school in English (note: don't do this: https://jakeseliger.com/2012/05/22/what-you-should-know-befo... ) and would hear this argument, I liked to observe that everyone, given the choice between getting punched in the face or having someone say something mean to them, chooses the latter. This would seem to me to argue that not everything can be reduced to language, even apart from all the other very good and obvious-seeming arguments along those lines.