Imagine how much better the world would be if the copyright term was shorter and/or if past a certain point, registration (and payment of fee) was needed to renew copyright and use the full term.
In an equitable world, LLMs would only provide answers from <=1930 data (as of 1 January).
Yet another argument for copyright being far too long.
I suggest looking at the https://publicdomainreview.org/ for a more comprehensive listings,
and this one for books:
https://standardebooks.org/blog/public-domain-day-2026