Again, why should their preferences automatically outweigh my preferences?
Because it's not a preference, any more than their name is a preference. You prefer to be wrong? That's fine, but understand that your preference is to be wrong. If you say "Arth is making a stupid argument again - she always does that" then you would not be pitting your preference against my preference, you would just be wrong.
I don't think it is against the rules. She's been doing this for a while, and hasn't been actioned for it yet.
That's because referring to someone who has a specified gender with a non-gendered pronoun isn't actually incorrect. Non-gendered pronouns can apply to anybody.
So if I change my preferred pronoun to "Darth", will you enforce that? Why or why not? It's no different from someone asking to be referred to as zi/zir. Or any other made up pronoun asking me to care enough about them to remember it. What exactly makes one of them "playing silly buggers" while another is a sanctionable offence?
"Darth" is a stupid example, chosen solely for its ridicule value. Zi/zir was actually a serious proposal that never caught on. See above.
People ridicule the idea of pronouns with statements like "I identify as a threat - my pronouns are try/me". It's stupid and all it does is to indicate that you only want to belittle.
I'm not sure what that has to do with anything. The chance may be small, but what is your position about what one should do in the event? Because it does happen, even if infrequently. Do you think one is obligated to use bespoke pronouns or not? Following your earlier logic regarding cross-sex pronouns, I would guess that you would say yes, but that's just a guess, and as far as I can tell you haven't actually said. So can you tell me your position?
It has to do with everything because one of the most common complaints about being asked to use the correct pronoun is that the person will be unable to remember the bespoke pronouns, which you'll notice is exactly the argument that is being used here, and which my statement is a reply to. In fact, you just used it yourself.
It's a spurious argument, because the number of people who use bespoke pronouns is, as I have said a hundred and one times now, vanishingly small, and the chance that you will encounter someone like that in your lifetime is infinitesimal. Not saying it will never happen, because you never know. But it's extremely unlikely, and it's not something that you have to take into account.