ClayMemory VS Polar Bookshelf

I absolutely agree with the general sentiment. Last year, I wrote my Master Thesis on how to easier create cards from PDFs (my introduction is basically this post :D). It really is a joke that a software has access to the pdf but we need to extract text (manually) from it to study it. My approach was a bit more classical: I tried to integrate new creation tools with a PDF reader (My prototype: https://github.com/LuccaHellriegel/ClayMemory). There is one "deck"-equivalent per pdf-page, an automatic-copying mechanism and context-menu for easier card creation and an origin-system, that links the position of extraction with the new card. Still a prototype (I have a laundry list of possible imporvements), but the prototype and my user study showed that there is so much potential here in making creation easier.

Its creator planned once to make it properly selfhostable before making it kinda proprietary I think. Maybe you could ask him again about polar-bookshelf and his plans to make it fully selfhostable.

book annotations: polar (integrates well with SRS)

“Some books are to be tasted, others to be swallowed, and some few to be chewed and digested; that is, some books are to be read only in parts; others to be read, but not curiously; and some few are to be read wholly, and with diligence and attention.” -- Francis Bacon

Mortimer Adler's How to Read a Book provides a decent framework for dealing with the variety of books out there. There are also tools like Polar[1] that provide an easy way to do incremental reading[2] which may help when attacking a book piece by relevant piece.

[1] https://getpolarized.io/

[2] https://en.wikipedia.org/wiki/Incremental_reading