In the world of digital art, there are actually people developing NFTs that are purely generated on-chain. It's still a relatively small school, but you can check some of them out here https://www.0xchain.art/
Almost all of these are just graphic doodles with an arty name, or low res avatars. They’re art in the sense of being made and appreciated by someone, but they’re certainly not worthy of being called ‘fine art’, or unique.
Yeah well, let's not open that pandora's box
Gatekeeping what defines art.... Not a great look even if I understand where you're coming from. But check out Cyber Brokers which is super detailed and entirely on-chain.