From Discover Magazine’s article People Have Used They/Them as Singular Pronouns for Hundreds of Years:
Battles of grammar, for the most part, play out in English classrooms and in the pages of style guides. Rarely do arguments over split infinitives and Oxford commas venture beyond the walls of academia.
My first thought at this point was that whoever wrote this article definitely doesn’t have my circle of online friends. Oxford commas in particular are a regular source of entertainment, especially the amusing images produced when the Oxford comma isn’t used. And while there certainly are academics among my friends, such posts definitely aren’t limited to that group.
But one linguistic phenomenon lands in the limelight every so often, and it’s a word you know well: the pronoun “they” — along with its derivatives “them” and “their.”
I don’t really expect that I have many–if any–regular contacts who are still prescriptivist about singular “they”; in my circles, it seems to be at or near universal acceptance. But this was still an interesting look into its history and usage.
Kirby Conrod, a linguistics professor at the University of Washington whose own personal pronouns are they/them, polls students each semester to assess their feelings about this specific usage of the word. Most have no objection; some, especially those who grew up using singular “they” with nonbinary friends, are simply confused — why would the professor ask about such a mundane word? “It’s really already hit the threshold of this critical mass,” Conrod says. “It’s part of the language enough that I don’t think you could squash it if you tried.”