Despite the actions of the Gillard government (who repeatedly refuse to legislate marriage equality but pushed through gender identity everywhere when no discussion), Australia’s Sex Discrimination Act clause 42(1) still reads as follows.
(1) Nothing in Division 1 or 2 renders it unlawful to discriminate on the ground of sex, gender identity or intersex status by excluding persons from participation in any competitive sporting activity in which the strength, stamina or physique of competitors is relevant.
oh, and pregnancy discrimination explicitly says “pregnant woman”, voluntary bodies can exclude people of a particular sex and so on.
IANAL but including males in women’s and girls’ sports and other facilities in Australia has been entirely a choice.
link https://www.legislation.gov.au/Details/C2023C00003