As an extension of this, only allow children to look at works they purchased publication rights to, lest their creative output becomes influenced by a different person's style.
Your suggestion would be accurate if we lived in a world where we all shared, and there was no money, and copyright didn't exist, but we don't.
But republishing any work as your own, probably falls into that category. And it isn't about profit, but commercial use; thus pasting onto a blog to improve your business (rankings, hit count) is a business use case.
These AI companies are making serious amounts of money (OpenAI is valued in tens of billions) on the back of artists who never gave permission for their work to be used in this way.
If a child took an artist's work, copied it and made significant amounts of money from selling it then yes they should be within the purview of copyright law.
the copyright aren't all encompassing. There's only an enumerated set of rights granted, and "this way" (aka, training an AI model) is not one of those restricted activities (like distribution or broadcast).
Unless the model can be argued to be a derivative work of the training data set (which i don't believe it is, since the process of training is sufficiently transformative imho), the original copyright holders of the training data do not need to be asked permission.
Maybe the AI needs to be able to print out a list of sources to provide attribution. That would be interesting.
that's the responsibility of the user said AI to check.