This perspective seems insane to me. I'm undecided, but if I were to put forward an argument that AI art will be bad for culture regardless of economic model, it would be something like "AI art will always be worse (in some way) than human art, but it will also be cheaper than human art, and thus will replace it in basically all commercial fields, which would be bad for culture." Maybe I'd say it's worse because it's inherently soulless, or just that as a practical matter AI is be better at doing the bare minimum than humans are, or something like that.

If I thought that AI art would allow almost anything to be produced by anything at incredible quality, at no cost and with little skill, that sounds like a Sci-Fi utopia to me, an almost unimaginable world in which all limitations on self-expression are lifted. A world in which making a movie or a TV show or a video game becomes a weekend project. It sounds wonderful.