Its a niche fork of a niche product that doesn't make money for anyone involved in making it. They don't care.

Considering it's already the first result searching "calibre without AI" it'll probably be fine. No one will use this who doesn't already know about calibre.

What would the difference be between it having one user and it having a million users? I doubt they are banking on getting mad donations, there are easier ways to make money.