That’s kind of the point I’m making — most people have it but don’t notice it because for most it is very minor
I think most use info-graphic watch face or similar and doesnt notice it because the background is black and they probably haven't touch the brightness settings. The problem is more or less visible when you use the lowest level of the brightness and scrolling the settings for example or using some other watch face than black - e.g. single colour watch face. So most doesnt notice it until they try something else..
After seeing so many complaining the uneven display I don't doubt anymore the reason why apple uses so much black on their watch faces.