Which gives us "they". This has been rejected as plural but when you don't know the gender of a person it is used for example if someone dropped something and you couldn't tell their gender you would say "They dropped their ....."
Colloquial English and written English are very different, though. Yes, we would say 'if someone wants to make a statement they can declare their gender', as 'someone' is neither countable nor gender-specific. In other words, 'they' is a generic pronoun that is useful when the number of people attached to it is uncertain, or the gender of a singular person is not known. It is jarring when we know that we are talking about is one person whom we know to be male or female, and we wouldn't say 'the woman over there dropped their pen'.
My cousin's daughter (can we say 'daughter'?) is non-binary, and referring to them as 'they', which I do out of politeness, does not come naturally, as each time I do it I am reminded that they are non-binary. This dissonance each time they are mentioned means that their non-binary identification has become the most important thing about them. It shouldn't be, if the whole point of being gender-neutral is that gender is unimportant.
The only way I can think of to get around it would be to have a new pronoun that is singular and gender-neutral (and another gender-neutral plural one), but that is not going to be achieved by forcing people to declare their 'identification status', as that just breeds resentment.
How would you advise someone who has transitioned to female, and is known as such at work, but hasn't told her family in Jakarta who still think they have a son, as he presents in that way at home? Should she have to declare herself as 'she/her' on her emails, and have the decision to come out to her family made by a university policy, or should she conform to that policy and deny her identity by using 'he/him'?
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