I don't understand why they say that "Japanese RPGs aren't as successful outside of Japan".
Based on VGC numbers, most JRPGs sell better in Americas than in Japan.
Quick examples on the PS3 are the likes of Atelier Rorona, Demon's Souls, Disgaea 3, Cross Edge, Trinity Universe, Last Rebellion, Eternal Sonata. Wii games like Pokémon, Fire Emblem: Radiant Dawn, Arc Rise Fantasia, Rune Factory: Frontier sold better in Americas. All 360 JRPGs I know sold better in Americas (that's more than 20).
you don't consider the amount of money they had to pay for ads that is so expensive as doing the game
did ark rise of fantasia sold?