Well the main reason is because westerners have a habit of doing something awesome, then moving on to the next big thing, not taking an original concept from ultima and milking it to hell. Its no surprise that it was a western developer to come out with LittleBigPlanet and practicaly redefine a console platformer, PC gamers were always this way for a long time, now since the first Xbox released console gamers are now thinking the same, most westerners prefer their RPG's as non linear as possible.
And turn based games require skill? not really, you press a button it fights for you, you wait for the enemy to attack you do it again, life goes down?, time to heal, repeat process, or in Final Fantasy XIII's case you push one button to chain all your future attacks together (literaly playing for you), no thanks.
Kingdom Hearts despite its real time battling system, is still on all accounts a JRPG, it was just as linear as the other JRPGS with a real time battling system i don't know why some people think its not a JRPG just because it used real time, i think you wanna try a series like Elder scrolls vs the typical FF game rather than KH.
Replying to the JRPG's having tougher bosses, its not that they are tough its that they SEEM tough because you will get hit every single time, one boss on FFXIII swung a sword that took 98% of your health down and you couldn't avoid, and other bosses would cast spells on you that kill you when the timer goes out, they aren't tough its just that you cannot avoid their attacks unless you use spells, buff yourself up or debuff them and what not, they make it seem tough because its gameplay is so linear you are forced to be hit. it doesn't require much work on the developers part making a tough boss when you can't avoid an attack and they overpower them too hell, i call that cheap.
I used that Vanille chick or w/e the hell her name is, on the boss to debuff him, and i killed him in like 30 secs, this was the last boss too, fastest boss i ever beat.
