They don't slice up the world the same way you do; whoever made up that word put gays, lesbians, and transsexuals together for political reasons, and left-wing political activists your median chan-users are not- why use the language of someone else, someone who despises you and wants to crush you?
From their point of view, the mental theatre that contains actors named 'LGBT' and 'Diversity, Inclusion and Equity' as front-and-centre characters is a cold, dead place-
whereas their native memescape, filled with Colourful Words, traps, arguments, the cacophany of 'hateful memes', is alive and vibrant by comparison, if tinged by a deep despair at the leaching of vitality from the world.
It's why the NPC meme caught on.
Traps are anime, and so are idealised abstractions as much as anime girls are. They're also tinged by imported japanese culture, I'd assume.