What TV do you have?
I know my entry level Samsung TV (NU7100) has terrible HDR, and it's only getting worse with subsequent models. (according to RTings)
Going from a 4ms to a 1ms response time monitor, I can tell you that it makes a big difference as well. That, and of course 120Hz+.
My monitor supports HDR, but I haven't played a game that supports it yet.
Now I just need an RTX capable GPU to claim my position in the PC Master Race, (defeaters of the console peasants, masters of the input devices, users of mods, players of the most and best exclusives and they who experience superior graphic settings in the past, present and future - bow down before them) again.