That said, singular-they is pretty much the best alternative to dealing with a number of issues that copy editors have struggled with for years.
Like "Theya".
Theya is my friend. It's singular, non gendered, and then we can just get rid of every pronoun except "they" and "theya".
https://en.wikipedia.org/wiki/Part_of_speech#Open_and_closed...
This really just a way of rephrasing what the parent comment says. By some reckonings, in English, pronouns are a closed class, and verbs are an open class. Some languages have it the other way around, where you can invent new pronouns but not new verbs (you have to take a noun X and say “do X” or something like that).
But honorifics are tricky and some people feel very strongly about them--e.g. Dr. for someone with a PhD.