It shows the one person can straddle 2 identities (or more) at different points in their lives.
According to the segregationist philosophy being touted here those people, at their most vulnerable points, should be made to feel unwelcome in their community.
You appear to want to 'ungroup' them at the time they are probably struggling the most.
You appear to want to pit them against their former or future identities.
If a person who previously identified as a transman now identifies as a lesbian do you think they suddenly care any less for other transmen and their rights? Or can only conceive that because they feel that a lesbian ID now fits them better that every transman out there is misguided?
Human groupings and their fights towards rights are not about reductive concepts but the varied and complex people that form them.
Yes, people can have different "identities" but we are not talking about identities.
We are talking, in this context, about people who are attracted to people of the same sex. As opposed to people's gender identity.
Someone could certainly relate to both of these things. A male person who feels a feminine identity - a transwoman - could be attracted to other male bodied people. In that case the person would be both homosexual and trans. This was, in the past, why transwomen were often found withing gay circles and lobby groups. A tranwoman attracted to women, however, would be heterosexual, and would really not have more relation to gay men or lesbians than any other male heterosexual.
Sexuality isn't about identity. Some gay and lesbian people do have a stronger sense that they see themselves within that kind of framework, but the identity isn't what makes them gay or lesbian. And lots of gay and lesbian people have no interest in their same sex attraction as type of identity - it doesn't change their attraction though.
There is no more logical reason to attach lesbian and gay social or lobby groups than there is to add disability or race. There isn't a logical connection, even though there are some people who may be black and gay or disabled lesbians. (And for that matter you could, and people sometimes, do, separate the lg and b, where the interests of each group are not aligned.)
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