How about Cloth Physicks?

[Culfinrandir]

Probably due to contract that was made before SE even considered making a PS4 release. Maybe they didn't expect it will go so well.
But when i read about new features, and there was HBAO+ i was kind of surprised.
Quess they starts to think about serious graphical improvments over next expansion.

Thou indeed Cloth Physics may not be included, until Yoshi will clearly state, that next expansion won't cover PS3.

Cloth Physics is also part of GameWorks & could easily be toggled to ensure it only operates on high end systems. The real limitations of FFXIV is that the developers chose, after the failure of 1.0, to always cater to the lowest possible denominator. The result is that a huge amount of advancements made since release are ignored.

As a side note, I disabled HBAO entirely on my AMD system & found an improvement in both graphical quality & framerate along with it making the game more stable.

[Felis]

You just said it yourself - TEN YEARS! That means that at least some of the design or system is a decade old. That's one of the issues with FFXIV too in my opinion, it's using an engine that's from 2007 (Crystal Tools) which itself began creation in 2005 for FFXIV on DX 9.0c.

1.0 used Crystal Tool, not ARR. The devs changed the engine for the rebuild.