I'm not failing to understand that, I just don't think it's an insurmountable barrier.

You could overcome it through various means, including helping to set up a clearinghouse for bulk rights, implementing a data clean room approach that models could train on in situ, lobbying Congress for copyright law changes especially around orphan works, using Section 108 of the Copyright Act to set up a specific preservation vehicle like the HathiTrust, and other options.

I find it ridiculous that so many in this thread are acting as though AI companies are simply powerless to do anything but buy up and destroy these rare books.