> but would have sounded absolutely bizarre and ungrammatical to most native speakers (regardless of literacy/education) before the movement for gender-identity

> but would have sounded absolutely bizarre and ungrammatical to most native speakers (regardless of literacy/education) before the movement for gender-identity inclusiveness became mainstream, because people didn't really conceive of the possibility of knowing a specific person but not being able refer to them as "he" or "she". I strongly disagree. I don't think responding "Oh, what did they want?" would have ever sounded bizarre or ungrammatical even if this was decades ago and everyone knew that Joe was a man. Language isn't always literal. Using a singular "they" (a pronoun normally used for an unknown person) instead of "he" in that context doesn't necessarily mean the speaker literally doesn't know if Joe is a man. It could just as easily be a subtle way to indicate that the speaker doesn't know Joe very well.