What Brian I believe is trying to point out, is that the differences that may exist due to time, place and culture, are minor compared to the realities and truths that exist in the world, which include the ability of our biologies to see and interpret visual data so that we may live and work
in that world.
If a lion was headed straight for you, teeth bared, pretty much people from every culture and place on earth would see and interpret the visual data sufficiently similar, that cultural difference are of minor consequence compared to biological and physical similarities.
More important, those similarities exist because there is actual truth out there, which our incredible biology is capable of discerning. We would not have survived were that not the case.
So the universal qualities that make great works of art .... great.... are based ultimately on the ability to discern and communicate truth, and not some culturally subjective distortion of some nonexistent fabrication of hopelessly subjective human beings.