In my experience, people justifying their own piracy usually think about it in terms of refusing to give money to unethical/monopolistic publishers. The fact that it results in money not going to the author is sort of abstracted away, by the fact that the publisher is in between. (Some also walk the walk and donate to the artists and authors directly in some way, but many don't.)

The AI arguments I've seen are instead usually justifying it like this: "We're democratizing those skills. You shouldn't have to learn art/writing/coding or pay someone else in order make what you imagine. Therefore, training AI on pirated stuff is worth it for the greater good." So the fact that it will result in artists not getting paid is unavoidable and much harder to ignore in that line of thinking.