Sex-segregation in sport relies on embedded notions of gender-normativity to assert that there are immutable advantages offered cis male bodies and corresponding disadvantages for cis female bodies.
As a result of the racialisation of protection, the MMA community (coded as white men) must intervene in Fox's case to protect cis female fighters (coded as white).
Notice Hass's insistence on labelling testosterone as 'male chemical mojo' despite the fact that she concurrently acknowledges cis female fighters as naturally possessing more testosterone than Fox.