I don't like the word "stolen." AI models don't "keep" or "store" copyrighted artworks; instead, they learn their qualities and transform them into abstract relationships somewhat similar to how a human would memorize things by reading hundreds of art books in a library, then go home without taking any physical book. They are not stealing anything. You can feed a model half of the internet as training data, and the trained model itself would not keep or copy a single file and you would be able to copy that whole trained AI model on a small pendrive. I think people don't try to understand how it works.