Is it really destroying though? They're digitizing them, and publishers still have the digital copies ready to print more at any time. So it's not like they're destroying the texts, they're just shifting them.
Nobody complained when Google did this over a decade ago 🤷
When you say they're "destroying the books" you make it sound like they're erasing one of the last known copy of some important work when in reality, most of these books were purchased in bulk from bookstores and libraries that were planning on discarding them anyway.
Almost all these books were either headed to the dump or the recycling center. They're just being digitized on the way.
Big AI mostly switched to synthetic training data anyway. The books they're digitizing are being used to gather knowledge, not writing styles or logic (mostly).
As in, when you ask ChatGPT how long some book is, it can just go check (if it's in the database). It's also useful if you ask about that book or about knowledge contained in that book. It'll even reference books now (if you demand that in your prompt).
It's not the same as earlier LLM tech which relied on scanned text to figure out how to respond to any given prompt (from a language standpoint). The "language" part of LLMs is a solved problem now (thanks to the synthetic training). At least for English 🤷