She's not being banned from participating. She just has to prove she has the testosterone levels of a cisgendered woman, and if she doesn't, she must get the level lowered. According to the ruling, if a woman has above a certain level of testosterone in her blood, the level must be lowered before she can compete. Seeing how testosterone levels are what causes secondary sex characteristics in men, and also the main reason why men are much stronger than women, this makes complete sense to me. The ruling's press release claims: Assuming this is accurate, and a woman has testosterone levels above 5 nmol/L due to one of these reasons, AND it gives a significant advantage, having the athlete take a pill to be eligible in competitions seems okay to me. I mean, when someone takes steroids, they're literally just injecting testosterone into their blood. If a woman has some medical condition that make her testosterone many times higher than normal, it's a pretty significant advantage. Like, arguably as much as taking steroids. No female would have serum levels of natural testosterone at 5 nmol/L or above unless they have DSD or a tumour.
(b) she must reduce her blood testosterone level to below five (5) nmol/L for a continuous period of at least six months (e.g., by use of hormonal contraceptives); and (c) thereafter she must maintain her blood testosterone level below five (5) nmol/L continuously (ie: whether she is in competition or out of competition) for so long as she wishes to remain eligible. This seems such a weird and arbitrary determination. So a male record-holder could legally become female or intersex, artificially lower his/her testosterone levels, and sweep? It's doping in the other direction. XY/XX is so simple. It's what causes testosterone differences.(a) she must be recognised at law either as female or as intersex (or equivalent);
If we use chromosomes, what about a person who was born intersex, and does not have a distinct XX or XY? Born XY? Sure, rule them out. Born with an indeterminate sex? Testosterone levels must be sufficiently low. Besides, Could such a person sweep after lowering their testosterone levels for a continuous period of six months or longer? I'm not so sure. At an elite level I'd think that would make an enormous difference.