I've made it clear that it was ONE of the reasons. And Monster Hunter, huh? Well, since you're listing ports: Persona 4 Golden, Tales of Innocence R, Metal Gear Solid HD Collection, Disgaea 3, and, outside of ports, Gravity Rush. I'll give you NSMBU as the ONLY AAA title the Wii U has there, but that's it - just one. Otherwise, to suggest that the Vita's current Japanese library cannot be compared in terms of strength, quality, or commercial potential to that of the Wii U is being extremely lenient and generous to the Vita's current woes. Furthermore, the Wii U's struggles is consistent with the current nature of the Japanese console market and with the performance of its competitors, which is a perfectly sound excuse not extended to the Vita by virtue of it being consistently mauled 5-to-1 by its competitor.