I guess I must be coming across as writing some untranslatable alien language...
The only monitor pretty much guaranteed to not suffer this issue is an old school CRT. That means cathode ray tube. You know, those old, super heavy monitors more resembling a TV from the 80s.
If you were to try a whole room full of digital screens, this issue is likely to be present for all, unless some particular de-banding option were to be built in. Or, perhaps, if one adjusts contrast and brightness outside the norm. Such as making the darkest parts of the image go totally black (and thus losing shadow detail and so on.)
Digital displays are inherently unforgiving of the finite steps in tone/hue when contrast in the image is quite low. A greater bit depth in the video stream, and the capability of the monitor to display it properly, are the base cure.
In the meantime, marcost has pointed out that Reshade offers a de-banding effect. I've not tried it myself, due to already using two other effects and not wanting to add more. But out of curiosity I just might see how it works (if my 3 year old version includes it.)