I think JRPGs flooded in because, until the days of HD gaming, they were REALLY easy to make. A turn-based battle system removes 98% of the player doing something to break the combat of the game by accident, meaning you're basically just managing scripting, data and assets.
The real problem is that JRPGs (and largely RPGs in general) exist on the back of a good story, and I haven't seen too many JRPG stories as of late that weren't horribly cliched, poorly translated or both.