After my recent experience I describe here:
https://ledstrain.org/d/2131-potential-correlation-between-video-timings-and-flicker/5
where I had to admit my original assumptions were proved to be not entirely correct, my newest theory is that many of the issues we experience with monitors (not those that are caused by graphics cards and PCs) have their source in pixel inversion. QC is getting worse and worse and pixel inversion is exactly what requires fine tuning of EVERY SINGLE monitor that manufacturers produce. Which might make sense why we believe these issues are more serious with recent products.
Once again what I saw: one of my laptops has an IPS screen that was perfect for me, even with Win 10 it was producing a very stable image. Unfortunately due to the issue I describe in the post above the screen started to flicker - it was a very obvious strong flicker. But the screen started to recover, the flicker was less and less noticeable as the subpixels were recovering in the damaged direction. When the flicker was obvious it was of course not pleasant to look at the screen but was causing no eye strain. However later on, as it was getting better, I can no longer see the flicker, but I am getting the VERY SAME symtoms as I am usually getting from screens that are not OK for me: eyes burning, feeling of nausea.
The difference here is that with every monitor where we all feel these symptoms we never know what's really going on. Here I know. The flicker was very visible at first and was getting slowly better every day. So I am very sure that what I am getting now is a very tiny flicker that is not perceived as such by my eyes, but it still produces unstable image which is not considered OK by my eyes or visual cortex (which is expected: flickering is not what our brain was built to see, but of course everyone has a different threshold).
For me this is the final proof that at least all my issues are caused by flickering. Some of it is caused by pixel inversion issues (which is what I'm getting with that laptop screen - it basically has a pixel inversion issue now) or caused by output from graphics cards. Sources may be different, but it is flickering.