Removing drm from files is an issue unrelated to booklore. Audiobookshelf is the same-you use another app if you want to play your audible purchases where you want.
Drm hacking is a problem created by amazon, it should not be the central feature in a good media management app.
Booklore is the Plex or Immich of e-books. A beautiful, self-hosted way to manage and read your own e-book library. But while movies are easy to rip from physical media we own, it's a lot harder to do the same for a book, making Booklore a pipe dream rather than a reality for those wanting to operate on the right side of the law.