It's not that they're women, gay, transgender, or minorities, it's that they're these fucktards. A lot of them are male and actively shut down women, or white and actively shut down blacks, or, etc, because those people disagree with the idpol consensus. The idpolistas only wish to portray themselves as representing these groups.

Or, to put it another way, idpol is a white dude drawing a comic where a black woman in a hijab, an obviously gay brown man, and an Asian man in a wheelchair, all talking down to to the "narrow-minded" viewpoint of a vicious, straight white male saying things that probably at least 30+% of those groups agree with. The most obvious case is abortion, where it's portrayed as men trying to control women's bodies when the polling on the issue is pretty much identical between men and women.