@Whatwouldbigfatfannydo sums it up nicely.
‘It's a big pile of nonsensical, farcical idiocy.’
We’ll look back on these times, I hope, as some form of existential crisis of a highly privileged first world culture.
As a seasoned feminist (C20th edition) for me, use of they/them was an quick adjustment of speech to counter gender assumptions that a role or attribute was exclusively for either men or women.
In those times, sex was what you were born as I.e. male or female, sexuality was defined by who you fancied or had sex with (already controversial e.g. bi-sexual, celibate homosexuals) & gender was about stereotyping roles & attributes based on or allocated to a sex, e.g. pink for girls, blue for boys, the surgeon is male, real men eat quiche, women are not technical etc.
Most people got the gender distinction.
Where things became skewed is when gender was used as a term in academia to define sex, this error has become commonplace, & is now being hard coded in to everyday use.
Sex is binary - male or female - except for the very few born with a form of chromosome variation & the response to sex-related hormones. In this case, the exception proves the rule.
In such complex cases where is ambiguity, a sex may be ‘acquired’ or given for the purpose of birth registration & other matters until the child has matured. Interestingly, this is being played out in the international sporting arena about female athletes with the intersex condition hyperandrogenism.
So, sex is not about feeling male or female. How one feels about being male or female may be a consequence of interpreting the expectations, social mores, attributes defined by gender roles. So gender-neutral to me is more inclusive, something that is not specific to men or women, & equally applicable to men or women. Gender-neutral does not mean without sex.