The OLED screen is arguably a downgrade because it uses flickering PWM brightness control.
See here for more info: https://en.wikipedia.org/wiki/Pulse-width_modulation
Not sure how specifically it's done for OLED though.
I don't believe it exists, and I place this in the same category of people who think that wifi makes them sick.
The problem is phantom array effect artifacts when you move your eyes. These appear and disappear in response to eye movement, so they can be perceived as motion, which is distracting to some people. I personally find PWM very obvious and annoying, but I suspect I have unusually weak saccadic masking.
Is this intrinsic to oled, or will future versions be able to avoid this?
You may not be bothered by it, mind you. I just tend towards dry/sensitive eyes and don't want to aggravate it.
However, you can use reduce white point and a higher brightness at night to avoid the flicker. Can be triggered with accessibility shortcut.
That's not to say no one can be bothered by it. But it's much less likely to bother anyone. I have sensitive eyes and tend to notice flickering at anything less than ~70hz. My Xs hasn't bothered me and I tend to use very low brightness even in well lit env.
I have seen the videos (especially review videos) where the flicker on the camera is present from another camera, but I haven't noticed any eye strain or any problems with this device. If anything, I'm using it more than my previous ones because reading text on it is so enjoyable with the better screen.
The main people affected are those who get headaches, would you say? Maybe I should reconsider.