Copyright doesn't apply just to stuff copied verbatim though, it applies to a lot more. It really doesn't matter if it is or isn't stored verbatim. Translations and derivative works are not exact copies and still fall under copyright. Copyright even applies to broad things such as "a concept of a character" and this can result in some pretty strange arguments some copyright holders might use, such as "Sherlock Holmes that doesn't smile is public domain, but Sherlock Holmes who shows emotion is copyright infringement" as described here.

It doesn't matter if an exact copy of the book was made. It matters if the core information that book carried was taken as a whole and used elsewhere. And even though the data was transformed as statistical information, the information is still there in that model. The model itself is basically just an "unauthorized translation" of hundreds of thousands of works into a very esoteric format.

The whole argument of "inspiration" is also misleading. Inspiration is purely a human trait. We're not talking about humans being inspired. We're talking about humans using copyrighted material to create a model, and about computers using that model to create content. Unless you'd argue that humans should be considered the same thing as machines in the eyes of the law, this argument simply doesn't work.