If "the only platform that supports DirectX" you mean "Windows", and therefore that "only games that run on Windows" means what I imagine it would have to, then

If "the only platform that supports DirectX" you mean "Windows", and therefore that "only games that run on Windows" means what I imagine it would have to, then... well, I for one don't think that's a problematic sample to draw conclusions from. In fact, if you want to get an idea about video games, especially (but not only) ones that run on computers, this is actually one of the better samples you could pick ;)