How do you stay in the know about this kind of stuff?
By being terminally online, I guess?
More concretely, I've spent (probably too much) time on Slashdot, Reddit and now Lemmy over the years (subscribed to Free Software and privacy-related communities in particular). Also, looking through sites like https://awesome-selfhosted.net/ and https://www.privacytools.io/, wiki-walking through articles about Free Software projects on Wikipedia, browsing the Debian repositories, etc.
I'm sure there are plenty of things I haven't heard of either, though.