A family member of mine didn't see the point of 1080p. Turned out they needed cataract surgery and got fancy replacement lenses in their eyes. After that, they saw the point.

Needing to define "perception" is a much weaker criticism than "isn't a thing and doesn't make sense".

It's easy enough to specify an average person looking very closely, or a 99th percentile person, or something like that, and show the statistics backing it up.