Many were out of print or were used copies, so they weren't books you could simply order new from a publisher. They are out of print. Anthropic deliberately sourced large quantities through used-book sellers such as Better World Books and World of Books and destroyed the physical copies after scanning them.

If you find this a "breathless emotional take", then I don't even know what to say. Nothing will meet your "evidence" criteria to dislodge your fervent fawning and support for destruction carried out by AI corporations.