What would be the point exactly? FFXIV is already pretty damn optimized as it is. It runs on max settings even on some slightly older machines as long as they aren't potatoes.

In other games that were newer and more intensive, or having issues in DirectX I'd agree. But this seems like "Lets do this for reasons. Vulkan is new." FFXIV already runs on MacOSX and PS4. Hell it runs on PS3, though not for long (and Vulkan won't help it stay on PS3). The only benefit would be a Linux use. But everyone running Linux already has Windows or PS4 to game on (just a sad fact of being a Linux user).