Jeff hated the idea that he should Have to sacrifice himself because he was born with a penis. Women and children first seemed archaic and sexist. Yes females could procreate, but how would society be different if people could change genders given a few days...
Bring down the glass ceiling, Yes! Eradicate all orientation and trans phobia.. from now on, wanting to be a different gender will make you become that gender... some people became men, others became women. Many switch frequently, and still others swap at different stages of their lives...
Others became a third gender... androgynous... not male or female... like a Ken doll, but with a tiny hole to pee from.
People soon found that in wanting exaggerated traits they could have them, People soon found that everyone was an XXXYY chromosome... and could become any of several different men or women with a few days time and a strong desire...
Eventually a neutron star was discovered to be the cause but by then the transformation was complete, the radiation had washed over ever continent transforming ever man woman and child...
Puberty started by 9 for all, even boys and most stayed genderless throughout finding it easier than conforming to gender roles. years passed and long term gender based conventions came to an abrupt end once women started working as men and vice versa.... Homosexual and Heterosexual became irrelevant as soon as you or your partner could become different genders.