We're not talking about the expression of knowledge. What is used in AI models is the knowledge from that expression. That code is not copied as is, instead knowledge is extracted from it and used to produce similar code. Copyright does not apply, IMHO
So you can train AI on Disney Movies to generate and sell your own disney movies because "knowledge is extracted" from it ? Betcha that won't fly in the courts. Here is "Slim Cinderella" - trained and extracted from all Disney Cinderella movies!
Sure, you can do it illegally - by breaking the law and recognizing that you need to be a fugitive. You can give up civilization and live in the wilderness. People can do whatever they want on their 10 year old Dell as long as they don't sell/distribute products made from other people's true efforts.