AI mega corporations are not entitled to easy and cheap access to data they don't own. If it's a hard problem, too bad. If the stakes are as high as they're all claiming then it should be no problem for them to do this right.
This is not copyright as we know it. Copyright protects against copying, not accessing data. You can still compile statistics off data you don't own. The models are like a compressed version of the originals, so compressed you can't retrieve more than a few snippets of original text. Newer model train on filtered synthetic text, which is one step removed from the protected expression in the copyrighted works. Should abstractions be protected by copyright?