FFXIV already exists for macOS. In fact, Codeweavers ported it. Essentially, FFXIV for Windows was packaged in a customized Crossover 18.5 bottle and released. …and it is good. Very good. (No, really. Buy it now.). Unfortunately, short of a hackintosh rig, there is no way for Linux users to run that at all.
The thing is, that almost three years later, it is still CX 18.5. …and still using WINE 4.0 and all that goes with it. With the availability of WINE 6.0 and improvements to DXVK and MoltenVK, there’s a lot that can be made better.
Depending on every possible combination of factors, using CX 21.1 and updating DXVK and MoltenVK can greatly improve performance. …with FPS significantly over 60. Unfortunately, the out of the box install of the FFXIV launcher into CX does not work very well. So, not only do Mac users lose out on possible improvements, but Linux users still cannot install it at all.
HOWEVER, thanks to the efforts of marzent, seathsky, and others on GitHub, a launcher/patcher has been created that works properly, and they offer an installer script that can update both DXVK and MoltenVK to more current versions. So, you get everything, and then some. (( Does anyone know if all that works under Linux as well? ))
So, how to get started?
Grab the Free Trial or buy the Starter Edition. (I say get the Mac versions. Let Square Enix know we’re out there and support their use of Codweavers for the port!). If you like what you see and want to improve everything about it, visit https://github.com/seathasky/FF14-MAC_ModSupport
p.s. Edited for clarity