Why LGBT, and not LG and B and T separately? Everywhere (forums, reddit, 4chan, IRL) I've seen LGBT spaces, those groups bloody hate each other. Even in the safespace thrɛad on those fora examples of that occurred. So why go to the same spaces and bunch up? ls that an "enemy of our enemy" thing?
Wide-brushed grouping of sexual abnormalities, I suppose. Provides l concentrated community given relatively lower numbers? I don't quite understand it myself; at least the T vs. LGB. At first glance, one's on a self-identification/gender axis and the other is on an attraction axis. There's not much middle ground except from the outside looking in. However, I had a homosexual female friend who underwent hormone therapy. He's... still a homosexual. It was counterintuitive for me, but it is what it is. The brain is funny. Apparently one's attraction is grounded in their own gender which does provide linkage between the two on a fundamental level. Shame it's not the case on the practical levels; they've both got issues but I don't think they really share the issues apart from potential social acceptance.