I was very shocked by the Hou's action today and I am not sure if this is a good way to protest.
Pairing is determined by the result from last rounds. Players with the same result likely to play against each other. Since this is a very large tournament, there leaves some rooms to play around pairing. I understand Hou that it is highly unlikely 7 of 9 players she played against are female, especially considering there are much fewer female players in the tournament.
I believe Hou is trying her best to reach 2700. If success, she will be the 2nd female player to do it. When playing against female players, whose rating is much lower than her, she will have to win. Even if it is a draw, she will lose rating points. Also, even if she wins, she will not get too much rating points (maybe 1 or 2, very slowly). It is quite difficut for her, as the goal of a lower rated player may simply try to draw her to gain some points. Chess now days is very easy to draw. I am not sure y the organizer chose female players for her. Maybe somebody just does not want her to reach 2700.
My 2 cents.