GrapheneOS and Techlore both have solid communities to use to learn about privacy but, there is a ton of intermingling between them and Privacy Guides so you may not like it.
r/privacy is a bit more casual but its mods are terrible and there is a ton of disinformation to sift through.
Its a private tracker for audio books, books, and book related things.
https://www.myanonamouse.net/inviteapp.php
Very nice community and the "interview" is simple. Not the psychotic hour+ long interview process that REDacted and other trackers have.