Hm I read the comments on the Kotaku site, and one person actually said something that is probably close to the truth. Japanese people like story-driven games. That's why rpgs sell so incredibly well, and fps don't. They even play games that are only about the story(dating sims etc.) Western people don't understand why they can enjoy a game that is simply only clicking through a story, but I guess those games do sell well in Japan because they have a story.
Most fps games hardly have a story. Even when some games tend to have a decent development in the storyline(for example, Half Life 2), it doesn't come near to any rpg when it comes to depth and the reason of the story. Fps games are generally about meaningless killing, while the Japanese people prefer meaningful killing.
I also wonder if this is just in Japan, or any Asian country. While I was in China I played Counter-Strike against a few Chinese people and they owned me. I don't play Counter-Strike much, but I am definitely not a noob anymore(I love to play this game on a LAN after all). So it looks like they do play fps games in other Asian countries, and also have a reason to train themself to become skilled in a fps game. Even when their gaming habits are quite similar, I guess the Japanese people are the only one who almost completely isolated themself from the fps genre.
Then again, (as also said in the comments), it would be awesome if they would create a fps game that is story-driven and has typical rpg graphics(yes, the anime-type). Once I played a Half Life 2 mod with anime characters, and I liked it a lot, so it would be great if a company decided to break the barrier and mix both genres.
Oh and I never had motion sickness while gaming, sometimes I do get a headache when I game for an entire day(let's say, over 10 hours without pauses), but I guess that is kind of normal.