Earlier quoted context omitted.
But isn't the whole thing asking someone to accept/endorse a different worldview? Is that really a tiny favor?
Calling the man "Muhammad Ali" didn't mean you had to convert to the Nation of Islam. Just call someone what they want to be called. You can do that without any endorsement of the reason behind their request. A "different worldview" doesn't give you permission to be an asshole.
The difference with pronouns/gender is that they depend on and proclaim external facts. ("She" is used for women and by going by she, I am a woman.) And by asking someone else to say that I am a woman, then really, aren't I forcing someone to change their definition of "woman"/"man"? Why do I have the right to force someone to do that?
Out of curiosity, if someone asked you to use plural pronouns for them, would you? (This is hard to ask in English, because "your" is used for both singular and plural subjects, and "they" has also commonly been used for both singular and plural as well, but imagine) What about pronouns in other languages? Do you really think that in communication, the other speaker shouldn't have any say in any of this?
I don't appreciate comments that suggest that someone you're discussing is an "asshole" for doing something you disagree with and don't think that contributes to the conversation.