If i recall correctly, apart from FF and DQ games the next biggest PS2 jrpg seller was Star Ocean Till the end of time with about 1.6 M a fair drop off,so large sales where the domain of the very few.
Production cost as impacted many games this gen but especially turned based rpg's one reason being that the genre didn't have the sales base apart from the aforementioned big hitters to sustain the increased cost's of making these games at a similar scale to there predecessors another reason was the strength and lower costs of hand held
gaming ,exacerbated even further by being felt strongest in jprpg's home market.
so you had a choice of either making a HD game with it's cost of not just money but also time and resources going from a large market to what was a small market at the time and with the PS3 in particular a lot of negativity
surrounding it or you could alleviate that risk by putting your games on the DS-PSP thus alleviating that risk some what, or if lucky be subsidised by MS not a long term strategy and you could turn to the PS3 latter on , that last part will probably turnout to be, go to the vita.
Research shows Video games help make you smarter, so why am I an idiot
