Maybe Sony could localise Ishin since after all they could release it as a PS4 exclusive in the West. But 5 doesn't have any sense or usefulness for them.
Well, consider this. Persona 5 is coming out in Winter 2014 right? Imagine when that's supposed to come West. Spring or Summer 2015, and that's a VERY generous prediction. And of course, Persona 5 is being ddeveloped for PS3, and Atlus is now under Sega.
Pleasing fans might be reason enough? I remember reading an interview where they mentioned they were creating a team that could work with publishers to help localise games.. something about pleasing small pockets of fans or something? Maybe it was just a dream I had.
You're thinking of this interview, you're not mistaken
http://kotaku.com/sonys-giant-list-of-video-games-1463345943