How did women loose rights for single sex sports in Australia?
A section from Dr Tracey Olverson's "A Collision of Rights"

"In 2019, the Australian Human Rights Commission, in consultation with the lobby group ACON’s Pride in Sport, released Guidelines for the Inclusion of Transgender and Gender Diverse People in Sport. Little peer-reviewed evidence was presented as to why the inclusion of transgender individuals was now a priority over other identified problems to sporting access, such as homophobia, sexual harassment, racism or disability. Ignoring the potential conflict between sex-based protections and gender identity and Australia’s international commitments under CEDAW (Committee on the Elimination of Discrimination Against Women), the AHRC’s Guidelines elevated the issue of transgenderism in sport over other pressing issues.

On 30th September 2020, in a sudden and unexpected public declaration, Sport Australia and the executives of eight major sporting codes, announced their new “inclusive”  guidelines for participation, focusing on transgender and “gender diverse” participants. Ostensibly, the announcement was designed to highlight the progressive credentials of Australian sporting bodies and to raise sporting participation across diverse Australian communities. In these new guidelines, diversity and inclusion are synonymous with transgenderism.

The 2020 announcement by eight sporting executives effectively erased the category of ‘women’s sport’ in their respective codes. In this announcement, the abstract, contested and ill-defined concept of “gender” superseded biological sex as the most significant protected legal category. As a consequence, the rights of trans-identified males to enter female sporting competitions, changing rooms, shower and toilet facilities, sporting scholarships and professional sporting memberships rapidly expanded, whilst the sex-based rights of female participants to safety, privacy, dignity, (religious) modesty, equality and access to sporting participation, rapidly contracted.
Female sporting participants were not widely consulted on these changes and no consideration was given towards the issue of women’s potential self-exclusion from participation on the basis of safety or privacy concerns. 
Importantly, Sport Australia’s Guidelines effectively enshrined the process of gender ‘self-identification’ - any man could now self- identify in to a female sporting category having undergone no hormonal or surgical interventions whatsoever. It was now the case that a biological male could participate in the sporting competitions of girls and women based on nothing more than his stated belief in his own feminine ‘gender identity.’ Female teammates would have to agree to include the biologically male participant, or else face accusations of transphobia and potential  prosecution for discrimination"