Yoshi-P is smart. I'm sure they'll look into a way to port the game over to the PS4 once it's more widely used. XIV may have more detailed environments and characters than XI, but it still lacks the volume of content. I rather doubt they'd have an easy, let alone cost-effective, way to revamp XI. And that's a revamp, not a simple port. I'm sure putting ARR on the PS4 would be much easier than having to rebuild the whole game.