While I'm strongly on team "train the AI on everything and reduce IP protections to strengthen the commons" as much as such a team exists, I think it's important to point out that this is a argument that misses the forest for the trees.
It's only relevant when taking a very logical/semantic view of the situation, when you take a more holistic view it breaks down. The scale and implications of the two things you're comparing are completely different. While I probably agree with you in general I think these sorts of arguments don't really help people understand our point of view because they sidestep the economic and social implications which are at the heart of this.
So many artists copy/adapt Disney's style totally anonymously for example. Should they be paying royalties to Disney?
As a human being, if I browse DA and reference other people's work/styles while I muck about on a graphics tablet am I in the wrong?