They bought, scannned, trained from, and destroyed millions of paper books, which was ruled legal. This lawsuit was for training from LibGen.
But if you don't want to ban them, telling them to buy one book of each, likely second hand, is complete pettiness that resulted in destructive scanning of millions of books, many of which were already practically available in digital form.
That's because the judges are supposed to rule on questions of law (ie. "is AI training fair use?"), not whether they think AI's good or not.