Eh, I didn't buy a true 120hz monitor for 3D.
If FFXIV burns up a PC that's SE fault. Bad optimization. Yes, the 60 fps cap and 30 fps cap were placed to prevent this from happening since beta, but that was because the original engine and overall server design stunk. The developers have already admitted to this. It's no secret.
I mean, FFXIV graphics are nice and all... but they aren't that nice. It's terrible optimization bringing your computer to its knees. Like you said, rendering objects far above and below what you even see on your screen hogging up resources pointlessly. I turn on ambient occlusion and I run FFXIV at 2 fps. I run BF3 on ultra with no problems. 50-90 fps and temps no higher than 55 degrees Celsius. Even on my gtx 460 768mb I could run far more demanding games than FFXIV well into 60+ fps (medium-high settings) under 60 degrees Celsius. It's not like we need an fps limit for other games on the market that are way more demanding than FFXIV (DX11 games). Why aren't those games frying machines?
The new engine that they are working on is supposed to alleviate these issues. If they need to cap your fps at 60 in order to prevent your computer from melting then they are simply putting a bandaid on a horrible mess of an engine to begin with. This is why they are building a new engine from the ground up for 2.0. We are playing on PC, not consoles. I expect to see fps cap on consoles simply because there is no work around for those systems. You are playing with what you have on a PS3. No upgrades and everyones machine is the same. But when it comes to PC, there are going to be a wide variety of set up's which means there should be a wide variety of graphical options for both lower end and higher end machines. Lower end machines can crank the graphics down to maintain playable frames, while higher end machines can crank up the graphics to make use of the hardware.