The poses are sexist in the sense that they perpetuate this stereotype for female characters. They contribute to the idea that female characters must look sexy in order to be interesting or appealing.
As long as this is not true for all video games you really don't have an argument. If all females presented in video games were of the sexy variety, then you could argue that the medium enforces a stereotype. However that is not the situation. What we have is an industry where it is common. At best you can argue that sexy women is common because the market make them popular.
As I pointed out earlier in the thread you need to think about if you want to argue against sexy women being allowed in media, or if you are simply complaining that something you don't like is popular. Unless you are arguing that it should not be allowed to portray women in certain ways (which I don't think you are), you are just arguing for something popular to be less popular. Now given that the video game industry operates in a global free market economy, what would be your suggestion to make things people like to buy less popular?
The simple way to make things you don't like less popular ir to simply not buy them. The interesting question is what you think entitles you to have other people have less of something they like but you don't? Women done >have to< be sexy in video games, its just common. So what?
