The intent behind Posie's poster was to assert women and girls' sex based rights.
Sex is a protected characteristic in the Equality Act. It's defined like this:
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11 Sex
In relation to the protected characteristic of sex—
(a)a reference to a person who has a particular protected characteristic is a reference to a man or to a woman;
(b)a reference to persons who share a protected characteristic is a reference to persons of the same sex.
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So I share the protected characteristic of sex with people who are women.
If woman now means potentially anybody then I share the protected characteristic of sex with potentially anybody.
So sex discrimination becomes no longer a thing because the bad thing that happened to me because I have a cunt and belong to the class of humans that are capable of pregnancy and childbirth (regardless of whether I, individually, am capable of these) could have happened to potentially anybody. The sex based exceptions in the EA that allow women only spaces and services as a proportionate means to achieving a legitimate aim must now admit potentially anybody.
Language is important. It's what laws are made of and it's also how we spread ideas.
There's a direct link between this mangling and repurposing of language, and situations like Karen White being placed in a women's prison where White sexually assaulted two women.
Or Girlguiding, changing itself by stealth from a single sex to a single gender organisation so that there may be a male bodied child sharing a tent with your daughter and you won't be told, and if your daughter has a problem with it, it is her who will be invited to move and probably offered some education.
Or your children being shown some bullshit mermaids gender scale in school, with Barbie at one end and GI Joe at the other, and asked to think about where they might fit on such a scale, with the strong implication that if their interests and preferences differ from the socially endorsed choices for their sex (aka gender) then they might not actually be a girl (or a boy) at all.
Or a woman specifically asking for a female nurse to perform her smear and turning up to her appointment to be greeted by a very obviously male bodied person who identified as female.
Or lesbians being pressurised to at least consider tw, even those who still have a penis, as potential sexual partners, and then to at least consider whether the cotton ceiling is evidence of their immense c*s privilege, genital fetishism and bigotry.
Sexual orientation is also a protected characteristic in the EA. It depends entirely on the definition of sex:
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12 Sexual orientation
(1)Sexual orientation means a person's sexual orientation towards—
(a)persons of the same sex,
(b)persons of the opposite sex, or
(c)persons of either sex.
(2)In relation to the protected characteristic of sexual orientation—
(a)a reference to a person who has a particular protected characteristic is a reference to a person who is of a particular sexual orientation;
(b)a reference to persons who share a protected characteristic is a reference to persons who are of the same sexual orientation.
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