I promise you that if FF became exclusive to Microsoft's next system, it would not sell in Japan. People try to dance around the reason why US consoles don't sell in Japan, ie "Doesn't appeal to Japan's taste, etc.
Wrong. They ARE that unaccepting of anything not Japanese. They would simply find a way to explain how FF has now become too 'westernized' to support. There's ALWAYS an excuse with the Japanese audience to hide their clannish and xenophobic nature. It has always been a part of their culture, dating all the way back to the meiji era. Sorry, just real talk.
But this is ok with me, because Japanese developers have realized that the only way they can exist in this day and age is to now develop for western audiences, simply because their own market has shrunk into irrelevance. So my how the tables have turned.
Their mindset has gone from an ultra cocky "for Japan only" attitude to a "how can we appeal to western audiences and make games like Halo and WoW" attitude.
And I'm ok with this. Why? Cause we will always have transcendental, badass Japanese studios like FromSoftware and Platinum who can hit just the right balance of east meets west in their games and give us more Dark Souls and Rising. The best will always stay true to themselves and survive in this market without whoring out their development teams to make more western themed games.