concernedcoder
This is useful information, because it does line up with the experience users on r/PWM_sensitive have with iPads. One user has been kind enough to test a ton of iPads and the ones with the gray flicker were uncomfortable and the ones without were fine. Interestingly the LCD iPads that were a problem had Liquid Retina screens (LCD screens without the notch).
This has to be FRC. The fact that the Studio Display gave both you and I the same symptoms as the M4 Air makes no sense other than they’re both 8-bit+FRC screens and I disabled Stillcolor on the Air and connected it to a Studio Display and it made no difference.
The reason I think this is FRC vs. PWM is because it’s present on desktops and monitors, pre-existing the M-series chip. It could be voltage leakage, too, but I think that it’s likely that is only worsening the temporal dithering that Apple is using at or below the 60Hz refresh rate.
So yeah, I’d agree with you it is a hardware problem in that at this point we can’t control the TCON or whatever is controlling the FRC and therefore we can’t fix these devices. The MBP MiniLED machines have PWM and FRC.
I wasn’t confident this was the issue at first on the LCD devices but the past few weeks we’ve gotten a lot of confirmation from many different people. I’m going to see if these pre-liquid retina laptops work for me this month, too. If it does then I have my answer, without a doubt.