To reduce it to its simplest formulation
Art has a duty to tell the truth ugliness is truth
i think the way people on twitter talk about "neoliberalism" is analogous to how i feel about this idea. it claims to be radical and revolutionary while conceding to a traditional understanding of things. "you're right to label my work as ugly because it's more dissonant that bach, mr. scruton. but hey, i'm weird, i actually wanted to make something ugly because that's more honest! what, you're still not interested in it?"
what's more radical in my opinion is to make an argument like luigi russolo's in
the art of noise, where he makes playing a bunch of engines in a concert hall sound like a perfectly reasonable thing to do. letting people know that contrary to the stupid old rules, it's safe to go outside.
the first part is undoubtedly a blatant strawman but still.
i don't see why you could possibly need art to tell people how bad the world is.