I guess it's now not "cool" to make fun of gays in rap songs? Damn... I guess rap really has changed, or might be changing.... People are so damn sensitive anymore! Pretty soon, you won't be able to even open your mouth and speak because something that you might say could be "offensive" to someone. Yeeesh, give me a break!
I would take it more as that the artist (Tech, Eminem, etc.) isn't gay, so they are poking fun at someone else by calling them something that isn't true... In this case, "gay". That's the way I look at it.