Silly people maybe :,)
Until the day come that AI can make something without a colossal human database of artwork done by human. Oh wait, that day will never come in theory.
Even if AI could somehow create without a database, it would still need human opinions to say "this is good, this is what I want". Some humans will still need to train it regarding selecting what is good and bad from its output, this method isn't the way to go though.
At the end of the day, look. If somehow, a software (AI) can draw my manga for me better than I can. You'd bet your dollar I'd invest thousands to own that software to use it. Alas, that day won't be here for a long time. Same with even just portrait drawings, you have very little 'control' when using the AI softwares that are currently available.
It's useful for like, the niche things that it is useful for. Like someone who isn't that versed in art, but needs a portrait for their characters, and even then. It'll look like most of the AI art, you can 'tell'.
With Blender and other similar software, even someone who cannot draw can just utilise a free source 3D model of an anime character, and pose it in certain ways to get their scene. You have so much more control to making a manga this way, it wouldn't be possible with AI. etc.
If we're just talking about like. Some of the stuff AI have produced, does it makes art done by human less impressive or less desirable? To silly people maybe. If anything, to most artists, I think it gives them more confidence as time goes on, seeing how AI is going. And I don't mean by how impressive results can be.
I mean, there is no 'soul' in AI art, even if the person who scripted the prompt has one. As impressive as some of the art that have came out of it is. AI cannot understand human emotions, it cannot replicate it, by extension, it cannot imprint those emotions into its art. There are certainly art that have came out by AI that makes us feel something, I don't mean to dismiss that. I mean, you can just press re-render, and you'd get another 'equally' impressive painting. Anyone with the prompt could. It is mostly aimless art.
Because if there is an 'aim', an artist could just draw it.
Edit: This is an article from the NYT regarding an idiot who submitted an AI art into a human contest to 'prove' a point. He did prove a point, that he's an idiot. At first glance, you have to admit, it is quite breathtaking. But any real painter can tell it is AI, the 'detail' that it meshes together near the portal makes no sense. No human would 'paint' that way, it is unnatural. When human paints obscurity in its detail, they don't do it that precisely. They just blah blah blah. not 1 2 3 4 5 6. You can go on and say it incorrectly painted some of the hands, 'cause AI aren't that good at anatomy yet.
My point here is mostly that. This was an aimless prompt. The software itself has no way of knowing if it had created something impressive. And if a person could somehow see the massive database of art that the software have access to, it isn't difficult to see what part of each image it pulls from to get this. Which is impressive for sure. As a mediocre painter myself, it doesn't worry me much though. When something can be created so easily, it devalues that something, no matter how impressive, if there are thousands like it, it isn't the same.
To get this printed out, and it is a beautiful thing. For sure, I definitely like it. But it's not the same as getting printed out an original work by an original artist. The 'value' is just different. I'm sure there will be rich people who see things differently, and buys the 'right' to an AI painting for mula dollars. But most reasonable people will understand differently. It's not the same as owning like, a Picasso. There is value to AI art for sure in sense of 'who' owns it. But I think the important part is, it will not hold the same value as human art, it will always be different.