We did not include filters for authors’ identities because we did not think we could do so ethically in the short time frame we had to build our vocabulary.
Assigning race, gender, sexuality, disability, and religious identity terms to other people is fraught with ethical questions. Assigning modern terminology to historical figures is even more complicated. At best, we could try to document our sources for this information, and require that our users do the same. However, we did not think we could build in support for such a requirement in the short time available to us.
(This site was built in about three months, while we were taking other classes. Also, pandemic.)
We would love to continue working on this project. If you have ideas about how to implement author identity metadata ethically, please get in touch!