Did they not use mountains of copyrighted material to train their models, and get away with it (fair use, greater good, blah blah)? What would suddenly prevent

Did they not use mountains of copyrighted material to train their models, and get away with it (fair use, greater good, blah blah)? What would suddenly prevent them from acting sneaky once again? Imagine sitting next to a river of gold and not being allowed to touch any of it. All that precious material, gone to waste.. Temptation! My guess is that they are keeping and/or are training on at least some kind of residual signal (metadata, vectors, ... ?), gray zone stuff that's not explicitly covered in their policies and can be explained away by an army of lawyers, if worse comes to worst. Machiavelli would nod approvingly.