That was due to negligence. Now it is profitable to keep the books private, and actively deny others access to them.

Ah, yes, because we all know OpenAI and Anthropic are famously just front operations for the high-end antiquarian book trade.

High-end antiquarian book traders is a genuinely hilarious way to describe them and I shall refer to them as such henceforth.

That's an in house operation that benefits them, not a front.