The singular they — that is, using the pronoun “they” as a non-gendered alternative for “he” or “she” — isn’t a new invention. In fact, it first emerged in English in the Fourteenth Century, according to the Oxford English Dictionary.
Next time you hear someone raising a fuss about the singular they — “it sounds weird” is the complaint I hear frequently — point out that the usage predates the printing press, the newspaper, and even Shakespeare.
Bonus fact: “You” used to be a plural pronoun. The singular pronoun was “thee” or “thou,” words that disappeared ages ago from English. Just more proof that language is a living thing that grows and adapts just as society does.