As short as I can, "Late Stage Capitalism" is specifically a concept from the writings of Karl Marx. They're literally communists. Communists post-Foucault hold that "culture" (of which language is a part)
describes reality in the way that a map describes a place - and as such, the people making the map control your perception of the place, the people controlling culture control your perception of reality. (This specific metaphor - language/culture as "map" of reality - comes from the opening pages of Baudrillard's "Simulacra and Simulation," which is the book Neo hides a disk in in the beginning of The Matrix. That film is actually a really descriptive allegory for a lot of these ideas - anyone can become an "agent" (as in, an agent of the cultural hegemony) because they are enacting the socio-linguistic programming that defines the hegemon's depiction of reality - and it's not a coincidence the writers trooned out.)
In this framework, individuals who possess
power create culture to describe reality in ways that benefit them. These people believe this is true across every social power metric. Individuals invent the idea of "sex", define themselves as male, others as female, assign privileges to those
identified as male, and impose that idea through culture. Individuals invented the idea of "race," define themselves as "white," define others as various subgroups (hence why you'll sometimes hear them say word-salad phrases like "individuals
racialized as Black"), assign privileges to those
identified as white, and impose that idea through culture. Individuals invented the idea of "property," define themselves as owning "capital," define others as proletariat, and use culture to prevent you from ever imagining a world without property so that you cannot realize the Revolution (which is inevitable as the End of History as prophesied in the Immortal Science of Marxism).
In the esoteric communist sense, the idea of sex as being immutable and biologically determined is part of this social construction of reality and part of the power-privilege matrix that presents you from realizing the Revolution (and this is true, of course, of everything - biology, science, math, everything. There's some really wonderful papers you can read that are absolutely unhinged takes on communist math or reconciling Marxism with thermodynamics. Really wild stuff.).
In the more practical Marxist sense, you see this in writers like Marcuse and Gramsci that "capitalism" "reproduces itself" (meaning, people in societies that work prefer to do things that
work rather than nonsense that doesn't, like communism), and in order to disrupt this reproduction, you need to disrupt the ability of those systems to work. Trooning the kids disrupts all sorts of stabilizing aspects of society, most pointedly the child-parent relationship, as parents cannot give their children normal parental advice about aspects of their lives because "the trans experience" is so far separated from what the parent experienced that very little is applicable. It is a novel experience (or, to quote some Queer Theorists, "an identity without an essence"), and so there isn't the thousands (if not tens of thousands) of years of experience in how to live one's life ("Is this teenage rebellion, struggling to define oneself as unique from their family and acquiring a distinct personal identity before ultimately returning to what works about their origin - or is this reifying trans joy?").
A few years back, before the widespread adoption of NETTL ("No Enemies To The Left," what Marcuse called Repressive Tolerance near a century ago), leftist internal slapfights would often feature the phrase "Read theory." Well, if you go and "read theory" you will quickly learn that the core of communist philosophy is, essentially, a religious belief that you can create a utopia by destroying civilization (to quote Kamala Harris, daughter of
Marxist economist Donald Harris, seeing "what can be, unburdened by what has been.").
You can understand communists by understanding that they literally want to destroy the world. They literally believe they're performing a ritual where they sacrifice
all that is for a heaven on earth that they believe is promised to them. Anything is ethical under that pretense. All evil is permitted.
