Changing the law and basically telling them "it's not yours, it's in the public domain" is such a punch in the face
...
You are basically saying that once you have created something (anything), it is free for anyone to use
This is a strawman argument. Almost no-one is saying you should be able to do what you want with other people's creative works,,
Most people agree that:
1) It is NOT OK to copy and distribute other people's creative works without permission
2) It IS OK to learn from other people's creative works, and use the knowledge gained to produce new, different works.
The question is, how much is it OK to get a computer to help you do 2), or indeed to automate 2) entirely. This doesn't seem to be what copyright law was designed to stop, but it's the only hammer people have to try to stop something they see as unfair (AI learning from other people's work on a scale no human could match, but not acually producing copies of it)
Personally, I put this in the same catagory as recording car number plates, or taking photos of people in public and trying to identify them. Historically, it's OK to do these things, but problems can arise if these are automated and done on a massive scale (and the results kept forever). They may be qualitatively the same, but quantitatively they are very different. I think it is OK for the law to do distinguish a person doing something on a small scale, and a computer doing the same thing to everyone and everything, everywhere, and all the time.
Ideally, I would want judges / juries (in any legal cases brought) to rule that AI learning from copyrighted works is not copyright infringement. And then government could decide if we, as a society, want to allow this thing. If not, government can pass new laws specifcally forbidding using copyrighted works for teaching AIs without permission. But I fear that is hopelessly naive of me :(