It definitely seems like JRPG's are all-around receiving lower scores. Maybe it has to do with the fact that the genre has more less stayed the same since the last generation. (although have do have more of an action slant in more and more games) If Lost Odyssey is released last generation, I have a feeling that it's average score would be closer to 9.
But at its core, the genre has generally stayed static for years. So for people who love the genre, a lot of them are still liking these games despite less critical acclaim. Whereas the more casual fan who has been playing all these Western Style games, they are finding JRPG's slower moving and less exciting then those from the West.
Look at Demon's Souls, that received a 29/40 from Famitsu but has a 89 average from Western Reviewers. It's also a game that looks like a game released out West.