The comparison to scribes is a perfect analogy. The 'scribing' of translating the idea of painting to an actual painting is being made more efficient. The actual creativity is what the original idea is, not the skill to put it on paper.
The value will flow to society via the cheap books (art). Value will also flow to authors (artists)[0] due to the facilitation of creation/distribution/replication. Where that value will come from is from the scribes (painters, sculptors, etc.)[1] whose contribution is rote.
[0]The intentional distinction here is that the value is in the conception of art, not in the execution of it in media.
[1]Imagine how much more productive Mozart or Beethoven could have been had an AI-powered orchestra existed in their time.