ESO is much less demanding than XIV but also worse optimized in some cases (at least on PC), i was playing at 4k60 when i had a single GTX970 (GTX1080 now), the improvement wasn't much if any compared to the 970, MMOs rely heavily on CPU, and my i5 doesn't really help.

Only in Towns ESO would drop to 30s, whereas in XIV at 4k i get high 40s, but i also see a lot more people in ESO, i guess because it's a Megaserver, i also don't think ESO has occlusion culling at all which is a MUST specially in MMOs.

That said, just because ESO got a 4k patch it doesn't mean it's possible on the Pro, either way the Pro should at least allow for more stable 1080p60, personally i won't buy the Pro unless FFXV gets stable 60FPS on it, which news surfaced today about it being like that.

Also, don't expect to buy the Pro, launch FFXIV and it will be faster, it won't happen, things need to be patched first, the only thing that could speed the game up would be a SSD and the Pro comes with a normal 1TB HDD