All art is subjective. Any attempt to "verify" a piece of art would be entirely dependent on cultural and personal sensitivities. Art isn't a math problem with a solution.
But you can dissect it into concepts and see if it is something truly new to the model - if the output contains things which aren’t there in the weights, you have a nice specimen to study and, crucially, a recipe to get a bunch of matrices to output untrained things.
This is like saying: All cooks are equally good, even the most disgusting slop (e.g. water/flour soup) isn't any better than a dish from a cook with several Michelin stars. Of course the latter is better. And if it is better, it is objectively better. Even if 0.001% of people prefer flour soup.