This is exactly like this for me (although I have a limited experience with Apple products):
iPhone SE 1st gen - ok, no eyestrain at all; older "square" iPhones I tried in the store years ago were also very pleasant for the eyes. But I could not stand a notched iPhone in the store (I don't know what version it was, as they are all equally ugly).
iPad 6th gen with TouchID - ok, no eyestrain at all, but I couldn't stand the iPad Pro 2018 screen in the store.
iMac 2017 - severe eyestrain. It does something bad to the vestibular system.