Yes. This is 'Mumsnet'.
Um.... what has that got to do with anything lol
"Lol"
Surely you can't be that stupid.
Most of us are on Mumsnet because we are mothers. Most women find that the point at which structural, institutional sexism comes home to bite them, hard, is the point at which they become mothers.
Whether it's being sacked while you're pregnant, the double shift (treble shift even) of paid work, housework and childcare, finding your pay drifts apart from your male colleagues, more recently the disproportionate impact of covid on women - sexism is rooted in biological sex, and that becomes abundantly clear when you become a mother.
My own equal pay claim was down to a toxic combination of long pay scales and the way performance pay and maternity leave were handled.
Sex, sex, biological sex. It had nothing to do with gender - whether I presented as a girly woman or a butch woman.
If you can't see sex, if you wilfully refuse to see sex, you can't see sexism.
You can't name the problem, you can't describe the problem, you can't fight against the problem.
And you can't identify your way out of the problem either. Those transmen having babies? Those "AFAB non binary people" having babies? Sex discrimination will bite them on the arse too. Because sexist men and sexist institutions always know who to shit on from a great height, regardless of how those people describe themselves.