I have no problem with Macbook Air Big Sur (2020), I can look at the screen for hours, but I cannot even look a few minutes at the screen on the new MacBook Pro M1 Monterey. I tried all the adjustments for the screen to no avail.

Someone at Reddit says the reason is that the screen is so smooth that the eye cannot focus. It's weird that only some people are bothered by this but I see enough complaints online for Apple to pay attention.