DSD is complex, but a lot of peer reviewed scientific analysis has been done that predates the current debate. I believe, happy to be corrected, there is a matrix that determines which DSD chromosome combinations are genetically male and genetically female and that is the sex recorded on birth certificates in the UK (potentially retrospectively). I would expect anyone with DSD should compete in the category that matches their true sex.
Everyone has a right to privacy and I feel for Caster and the other athletes who won 800 metres Medals in Rio, who allegedly also have DSD. But it is unfair for them to compete as women if genetically they are male. A blood test should enable all sports people to compete in the correct category for their sex.
WRT Trans women, genetically they are male and should not be competing in woman's categories. That doesn’t mean it is right to not respect their chosen pro nouns. However, if TW are disrespectful to women, by insisting they compete in woman's categories, use woman’s communal changing rooms and allegedly are exhibitionists exposing their male genitals to girls and women this should be called out.
This link boysvswomen.com/#/ is a factual comparison of the 8 female finalists at 2016 Rio olympics with USA high school boys.
What Posy is doing in calling Lia a man is the equivalent of the little boy pointing out the Emperor is as naked as the day that he was born.
Whilst not sports related between 2012 and 2018 over 400 transwomen used their penis to rape women. Their rapes were recorded as committed by a woman. This is not right or fair.
The law needs to protect single sex spaces, single sex sports etc. whilst also treating trans people with dignity and respect.