Why is my UHD Blu-ray picture so grainy?

[SunShines]

Hello!

I have a problem with my UHD Blu-rays. The picture is really grainy, especially visible on skin tones (close-ups look horrible) and white scenes (such as the Westworld intro, embedded below).

I have tried on two different players (UBP-X500 and UBP-X700), and three different TVs (Sony AF8 and LG E8, as well as an "old" Samsung F9005), and the problem exists on all combinations of these.

I have experimented a lot with the settings, and the only setting that reduces this grainyness at all, is the "Contrast" setting (and "Dynamic contrast"). However, even with Dynamic contrast turned completely off, and regular "Contrast" turned down to an unwatchable level, the grainyness is still there (although less visible).

The regular (1080p) Blu-ray may have some grain if I am specifically looking for it, but this is not noticeable at all.
The UHD Blu-ray is very grainy, and no settings on the TV are able to help it (at least not without otherwise ruining the picture). It is a major distraction to the movie.
Dolby Vision is ridiculous. Just ridiculous. The amount of grain in this mode looks like it was filmed on 35mm coarse sandpaper. None of the available settings are even remotely helpful to hiding these grains. Ridiculous.

As this happens across three different TVs, two different UHD Blu-ray players, all of my UHD discs, and all settings I can think of, I am now at a loss as to what to try. I even went out and bought new premium HDMI cables, but to no effect. Surely, it is not the UHD format itself that is this bad, or else everyone would have complained too. As I have quite recently upgraded all my stuff to 4K, my anticipation of a great 4K experience has been brutally shot down by this, discovering that regular Blu-rays are actually being displayed significantly better than my 4K ones. One friend told me to just be happy. "That means you can just buy the cheap discs and save money". Well, I don't want to save money, I want to have great movie experiences.

Does anybody have any suggestions to what I can try?
Thank you very much in advance!


(Also, how do I link to YouTube without embedding the video?)

Westworld intro