I remember seeing something about this on Wikidata and just not having enough hours in the day to comment at the time.
There are three issues being intermingled here:
*Sex, which is a biological marker determined by primary and secondary sexual characteristics such as breasts, penises, uteruses, etc. As such, the "sex" category is mostly correct, but should add 'unknown'.
*Sexual orientation, which identifies the manner in which the subject expresses their sexuality. This would include heterosexual, homosexual/lesbian/gay, transsexual, bisexual, asexual, pansexual, and a host of other variables.
*Gender identity, which is almost always male or female, but is not directly related to sex as identified in the first definition. Thus gender identity includes males who identify as females, intersex who identify as male or female, females who identify as male, females who identify as female, males who identify as male. Elements of sexual orientation may also play a role, as in bisexuals who identify as both male and female, or as neither male nor female.
It is important that assumptions not be made, particularly for sexual orientation or gender identity. Most notable people do not discuss their orientation or gender identity. I also would suggest that it be considered perfectly acceptable to leave those categories blank for the vast majority of subjects and include the response only where the subject has personally confirmed their sexual orientation or gender identity. Frankly, this is pretty much none of our business and is only notable where the subject says it is.
Risker/Anne