It's because of American law. If it were sane, everyone could share. Instead, if there are 25 copies of a book in existence, 25 different AI companies could buy them and pulp them. Woe be it if some company's lawyer has decided that they need to buy a new copy for each model they train.

Otherwise, I think it's good that books are being scanned. Please, AI companies, keep all of the scans, clean them so they can be compressed tightly, back them up to an insane degree, encourage your employees to make their own archives and share them with their friends, and leak them to libgen, annas-archive, etc.

The copyright law here is broken in general.

If there are only 25 copies and it's impossible to buy a new copy from the publisher, who's actually getting hurt if you "pirate" that book? How can anyone claim losses if they clearly don't want your money for a new copy.