What's the endgame?
Biological female dies from a bouncer bowled by a male, or a collapsing scrum where the front 3 are all male.
Woman's family sues governing body, or club, re negligence/corporate manslaughter/reckless endangerment of life or whatever, rather than the individual. Insurance companies start adding cleverly worded clauses to exclude cover for injury or death inflicited on biological women by biological males.
Governing body tries to change rules , or club team unilaterally starts refusing to admit biological males. Males sue re: discrimination.
Governing body or club thinks "fuck it" re insurance and legal headaches and allows women's sport to wither on the vine. Women's contact sport, and sport which is effectively partially contact sport (cricket/ fast bowling) ceases to exist.
Meanwhile, non contact women's sport becomes more and more dominated by biological males. It's a slower process but effectively women's sport at elite level eventually ceases to exist as it is populated almost exclusively by biological males. Women still compete at amateur, grassroots level albeit fewer of them; girls no longer have female elite role models to inspire them. Biological males still win a large proportion of these grassroots competitions.
A certain section of the heterosexual male population very briefly mourns the passing of women's televised tennis and beach volleyball, but is too busy wanking over internet porn to bother emailing a complaint to anyone.
A section of the population at large who like watching these and other women's sports for the skill, rather than tits and arse, is a bit put out but doesn't really care that much.
Women's sport dies; two men and a slightly bored dog attend the funeral.