Yeah, I've had issues with those devices as well. From what I can tell, it seems like there's a spectrum of screen flicker for Apple products, something like this:
iPhone 8 and earlier, iPad 7 and earlier: Mild or None
iPhone XR/11, iPad Air, iPad Pro 2018 and later: Moderate
MacBooks: Moderate to Severe
iPhones with OLED: Severe
This has been my experience, anyway. I've noticed that people who have issues with the lower end of the spectrum (iPads, iPhone XR, etc) also tend to be sensitive to the higher end spectrum devices as well.