Actually it isn't even fully about western RPGs.
The main change between the current JRPG culture actually traces back toward the rising development costs and dwindling returns of the traditional cinematic JRPG even in its native land, as well as the rise in popularity of Monster Hunter. The western RPG has grown in popularity, in part thanks to MMORPGs but the main switch from the old guard is the increase in technology, the difficulty to mask the similiarity of turn based combat and to make the games stand out when there are dozens of them out there with similar stories.







