"I'm a woman trapped inside a man's body"

It's weird when drag queens say, "I'm a woman trapped inside a man's body." How come that woman is always one who wears slutty clothes, 6-inch heels, and way too much makeup? Shouldn't it sometimes be a shy librarian type of girl that's trapped inside of them? You never hear anyone saying, "I'm a lesbian trapped inside a man's body...So I just look like a normal guy."

Update: Saw John Mulaney the other night and he did a totally similar joke. Maybe I heard him do it another time? I can't even remember but I'll err on the side of caution and drop this idea.