There isn't an issue. The reason GoT lacks diversity is justifiable for the franchise and the show has a lot of female characters in very major roles, especially the season airing now. A lot of the female characters are very cool and interesting too in my opinion. It's just people want to take offense to things they feel their public persona would be offended by.
Now if the GoT following has people like that, imagine the shitstorm that would occur if the show the creators and HBO are thinking about producing actually happened haha