The legacy of the nit-picking late 19th and early 20th centuries is with us still, in the form of armchair grammarians. You would think sometimes that the English language had been shat whole and complete out of H. W. Fowler’s clenching sphincter.
We’ve already talked about “literally,” and how it can mean literally any degree of literalism you want; now let me clarify another grammatical misconception for you: the singular “they” has been with us from the beginnings of modern English, and no one has ever been confused by it.
Chaucer used it. So did Shakespeare. Jefferson, Austen, Dickens, Thackeray, Shaw…pick a famous English-language writer, and somewhere in their works you’ll find the singular “they.” (See what I did there?)
And really, why wouldn’t English writers rely on the oldest and most common gender-neutral pronoun in their language? Taken as both a singular and a plural pronoun, “they” is just one more English word out of thousands with multiple possible meanings.
It’s not like there are better alternatives. English lacks a gender-neutral singular pronoun with no alternative meanings (other than “it,” and an emotional separation between humans and all other objects is encoded too deeply in the rest of the language to ever let that one catch on).
A purportedly gender-neutral “he” isn’t gender-neutral, obviously (try a construction like “everyone hates getting a run in his stockings on the way to work” to see the absurdity of it), and if we were to use a gendered pronoun as the generic, “he” has worse odds of being accurate than “she” in our slightly female-skewed population. If reducing ambiguity is your game, that’s not the way to go.
“He/she” has obvious readability and efficiency issues, and while more inclusive than one gendered pronoun is still not particularly representative of modern gender identities (which could be better shortened to “fuck it; who knows?”).
And perhaps the reformists who want a brand-new pronoun will have their day eventually, but the cause would be drastically helped by moving away from really odd and under-used English consonants that produce ambiguous pronunciations: none of us old farts give enough of a fuck to figure out what the difference between “ze” and “zhe” is, or how you say either one, and they’re both a pain to type. Until a very widely-read author or publication picks one option and throws all their weight behind it, those will remain an alphabet soup of wistful good intentions.
So until something better comes along, please — use the singular “they” with confidence. You could probably come up with a sentence where the numerical disagreement created ambiguity if you really tried, but it would be a tortured construction that no one would realistically use in their day-to-day speech.
See what I did there?