Political correctness is (in the words of Steve Sailer) a "war on noticing." Thus, it employs a form of newspeak, a political manipulation of language, whose purpose is not to make it easier to describe and understand reality, but harder.
Thus, for instance, the concept and language of race and racial differences is attacked not because it has no biological validity (it certainly does, just as much as species, sub-species, family, etc.) or use in the social sciences (it is predictive of all kinds of social outcomes), but because it is "problematic." In other words, it makes it easier to see truths about the world that are inconvenient for the state ideology. Newspapers hide the race of criminals not because the information is irrelevant but precisely because it is relevant--it is not just noise but meaningful data from which people can draw generalizations and inferences about the world. Disallowing such crimethink is precisely the point. In order to keep us from noticing that blacks and (to a lesser degree) hispanics have higher levels of criminality, we are to be deprived of the language necessary for describing it. (We even shame people into not using race in totally benign situations: "What's your friend's name again? ... you know, the ... uh ... tall guy with, uh, dark curly hair ..." To keep us from noticing patterns, we must be deprived of the general language allowing for classification.)
Similarly, the attempt to classify people who are confused about their sex with the sex they identify with rather than their actual sex is a confusion of language for the purpose of making it harder to think. I recently read the beginning of a book discussing women, which had to start with an extensive caveat/apology that, in describing women, the author was generalizing about human beings that, for instance, have female sexual organs and chromosomes, were raised as girls, etc., but, of course, we know that there are women who don't necessarily have these characteristics, so, what she said may or may not necessarily apply to all women. She then proceeded to make perfectly valid points about the class of human beings that everyone, everywhere has always referred to as "women"--and, which, by an amazing coincidence, had limited or no applicability to anyone else that might be included in whatever broader definition she had in mind in her caveat.
Biological sex is a pretty fundamental aspect of the human person. As evidenced by what this writer actually did, as opposed to her PC caveat, the words "woman" and "man," understood in the traditional sense are really useful for talking about and describing human beings, making generalizations and thinking about them. Changing those definitions to base them on the felt or declared identity of individuals rather than biological sex obscures reality and makes it harder to think about rather than easier. And, that, indeed, is the exact purpose. We are to be deprived of the language for noticing that "Caitlyn Jenner" is not a beautiful, courageous, woman but a ridiculous, middle aged man in a dress.
The intelligent feminists see this quite clearly. Letting biological males classify themselves as women (and vice versa) makes it impossible for them to talk meaningfully about "women's issues." If a "woman" beats up "her" girlfriend, is it still the violence of patriarchy? If a "man" kills his unborn daughter, is it still an empowering "choice" for women? If the highest paid "female" CEO is a dude in a dress, does this count as breaking the glass ceiling? Is "she" an inspiration for little girls?
In the hierarchy of victimhood, trans beats woman, so the feminists must give up the privilege of cis-normative language for the rights of their trans "sisters."
Insanity.
