I guess they can't have deeper meaning behind their work because to express deeper meaning one needs to actually have something deeper behind it. There is a skull on the table because...drugs bad? All the imagery just reinforces the central idea, that taking drugs is bad because if you're shooting, jesus is the one really getting high.

edit: My rambling actual point is that they can't really express things in the abstract, everything has to be literal. AI is incapable of abstracting deliberately, as it just follows a prompt, so it is likely that they like it for this reason, there is no deeper meaning behind conservative art, and there is no deeper meaning behind AI art.