It is though.
Your position is "Other than sports, CS should be treated as a woman because CS regardless of CS's actual sex, "Woman" is what CS believes CS is so it would be cruel to say otherwise"
Whether CS uses the T-word or not, that is the exact argument made for trans identifying men's right to appropriate and redefine womanhood to suit their emotional needs.
And my argument to both issues is also exactly the same.
Female people exist.
The word woman means something specific, and it's us.
Women only laws, rights, spaces and opportunities, including women's sports, exist because of the real world needs and capabilities of women, needs and capabilities we have because we are female.
To open any of this up to men because of how they feel is to change the basis of womanhood for all of us.
It changes womanhood from a recognition of the reality of our bodies into an assumption about our minds and how we feel about ourselves.
It changes the basis on which it's justifiable that we have women-only spaces and rights and protections and opportunities from recognition that our sex brings risks, challenges and injustices that it is fair and humane to mitigate, to a bundle of incoherent demands that basically boil down to "because it says Women on the door".
It turns our history from the story of the female half of humanity into the story of people who performed certain cultural stereotypes and through that derived identity and status, leaving the "why" of sexism and of misogynist oppression unexamined.
Accepting men (male people) as women for any reason, trans or DSD, is an act of debasement and rejection of women as complete humans in our own right who are physically different to male but absolutely equal in our human value and completeness.