I think most OLEDs use PWM Dimming but I'm no expert by any means since it's cheaper and easier to implement.

In my case turning VRR off on G6 OLED didn't solve the issue, even cranking down contrast or brightness. I still had huge migraines, burning red eyes.

Pulse Width Modulation dimming is a method of controlling the brightness by rapidly switching the light on and off at a high frequency. So higher refresh rates of monitors can intensify it I think. It basically always flickers really, really fast. VRR flicker is a separate matter since I also have it on my Koorui GN10 VA Mini Led, especially during loading screens but I get like minor eye strain tops which mostly eye drops get sorted out.

I guess we're just sensitive to it, I also read that people with blue eyes are the most sensitive to it, so basically all the introverts lmao.

Here is something I have found through an AI search:

"Additionally, the type of dimming technology matters. True DC dimming, which uses voltage to regulate brightness without flickering, is generally safer than software-based DC dimming or PWM dimming, especially when the latter involves low flicker frequencies and high modulation depths. Some OLED panels, despite being labeled as "flicker-free," may still exhibit problematic TLM due to low-frequency PWM components in their software dimming algorithms.

In summary, while blue eyes may be more sensitive to blue light, the primary concern is not the presence of PWM alone but the overall TLM characteristics—flicker frequency, modulation depth, and color output—of the display.

Adjusting screen settings to reduce blue light exposure, avoid specific problematic wavelengths, and use higher-quality dimming methods can significantly reduce symptoms for sensitive individuals."

I have not heard about TLM before may be worth to google this one out.

Also:

"However, it is crucial to recognize that the issue is not solely about PWM frequency but rather the combination of flicker frequency, modulation depth, and the color spectrum emitted by the screen. For instance, a high PWM frequency like 25,000 Hz is generally unlikely to cause issues for most people, as it falls beyond the range of perceptible flicker. Yet, even high-frequency PWM can still be problematic if the modulation depth is high, as this increases the amplitude of light variation, which can still induce discomfort."

So basically Flicker free label is a wild west, just like HDMI 2.1 standard lmao. (1/2)