I'm using a Mac Pro and an Acer 27-inch 4 k monitor.
In MacOS, I have scaled a resolution of 4 k, to 2560 x 1440 so that the symbols are not too small.
However, I can select in eso only a maximum of 2560 x 1440 resolution.
Only if I disable the scaling in MacOS, i can select 4k in ESO.
However I can see hardly anything on the desktop as icons and font are shown very small.
In all other Games I can select a resolution up to 4k.
Mac Pro 6 cores 3.5 GHz
1 tb ssd
24 gb ram
NVIDIA 1060 6 gb