The only counterpoint that I can think of is that sex is public information. If the form's request for sex is salient IRL, and the form-filer's sex will be app

The only counterpoint that I can think of is that sex is public information. If the form's request for sex is salient IRL, and the form-filer's sex will be apparent anyway, I don't think refusing or having an expectation of privacy about one's sex is reasonable. This is not the case for most things, but I do think it goes beyond dating.