If they implemented it, it might have to be a local setting that only you see.
Not because of any prejudice but because even if they wanted to do it, it would depend on whether it can be fitted into the existing programming - and the character data which seems to be pretty set in stone as to how many “display instructions” it sends to other players. It’s the same reason why we’re unlikely to get any other changes/improvements to the character creator options, or emotes detached from their strict race/gender variants, unless they do a major overhaul of the system.
At this point the character information would be something like “this is a [male] [Hyur]” and the system is programmed to look at the [male/female] to determine whether to insert “he” or “she” into the dialogue or chatlog messages.
In which case it’s likely that they can’t change that instruction to be “this is a [male] [Hyur] who uses [they] pronouns” (ie. adding an extra piece of information that the system wasn’t designed to handle, and doesn’t know to look at) and it would need to be implemented by changing what gets put in the male/female slot. Which probably means changing that top-level “choose your race and gender” page to have multiple additional options (probably needs six: male model/male pronoun, male/female, male/neutral, female/female, female/male, female/neutral).
And it’s probably not even as simple as just adding those options, because the current male/female instruction would be transmitted as a simple binary 1/0 (no pun intended) and changing that to transmit one of six different options would make it a three-digit binary number instead of one. Which again means changing the amount of character data transmitted, which might not be doable within the current programming.
I’m not saying all this because I don’t think your suggestion is a good one, just that it’s likely to be not as simple as “add an extra option!” when people have been wanting all sorts of extra options for years and none of them have been (can be?) implemented.