Epic post and reply!
I think the original games were called RPG's because of the mechanics we've discussed (story focus, statistical progression, looting), but also because of the fantasy. Even games like Shadowrun and Mass Effect fall under some sub-genre of fantasy. I guess anything tending to be a game could, but there's a clear literary background for these games as well as pen-and-paper precedents.
What I'm trying to say is I think the term is useful. But I also think it's pretentious for a developer to claim it for his own region when there's plenty of justifications for its application. I think that's like saying "RPG" is a certain type of video game, defined by certain conventions, despite the fact that RPG crosses different mediums.