I don’t think you’ll have to worry too much. Given that this will (hopefully) be a game with modern tech under the hood, there’s a good chance that D4 will support HDR or HDR10+ by the time it releases. Who knows, if Blizzard isn’t chintzy on the licenses, we may get lucky enough to even have good surround support or (gasp) Dolby Atmos support.
As someone with a heavy home theater investment (dual RTi-A9s, RTi-A6, dual TSi-200s, MicroPro 4000 subwoofer, Yamaha CX-A5100 preprocessor, and Monolith M7X amplifier w/ XLR inputs), immersive sound means even more to me than immersive graphics. 