> why can’t I take any code I find online and ignore the license terms and feed it into a compiler?

a compiler is not transformative. You translating a book into another language doesn't make it a new work.

But an AI that takes billions of images, and uses it to synthesize something different and new, is fairly transformative under my eyes, and deserves new copyright. Unless the AI generated image is largely composed of a small number of works, i don't see why anyone should have copyright ownership of such an output!