This could have all been resolved by just picking one gender-less pronoun to use for everyone.
Already exists: they/them
Non-binary people actively use it and everyone uses it in the singular when the gender of the person is unknown:
"Ah that driver in front is a lunatic, WTF are
they doing"
Some trans people hate it though, you could refer to everyone as they/them as it is universal but some transwomen specifically want you to say she/her and believe it's a microaggression not to, ditto to people with the weird neopronouns. Though in most cases you're only using pronouns when talking about someone so they won't know anyway lol.