Well, the world is a sexist place anyway and nothing is ever fair. The Amazing Race is undeniably designed in a way where brutal tasks will benefit alpha male teams and the all-female teams generally suffer. Some people (like me) generally like rooting for all-female teams to win because an all-female win again an alpha-male team will sort of be unexpected and beating the odds, and I don't really see this as sexist, I reckon for me it's I want to see unexpected things happening on the race. TAR 9 was a bore fest watching E/J and the Hippies dominate the race in alternative 1st and 2nd place.
But I do agree that some people don't look past the personality of the teams. I rooted for Max and Katie to win but am perfectly fine with Bates and Anthony as they were hilarious people who were easy going and seemed to be good-hearted.
The fact that people are complaining with an abundance of 5 all-male teams is because, the race is already sort of biased towards helping DECENT all-male teams progress further with physical tasks, and the fact that they are throwing in so many all-male teams without balancing it up is just disappointing. Had they cast 4 all-male teams, 4 all-female teams and 3 co-ed teams, I don't think there will be so much back-lash now. If you do some calculation, there's really only 8 female racers this season and it's pathetic, as compared to 14 male racers.