Kinda off topic, but I know a lot of people here use keybase for verification, but don't they have a slack alternative that's both free and private? (Assuming zoom didn't kill either of those aspects) Anyone use it as an actual slack replacement?
Perhaps I'm lacking context but I couldn't figure out your question and I'd like to help you find an answer!
Is this one Open Source too? I wasn't sure which project it was under. But if it is then maybe someone else can revive it because I'd love to have a Slack alternative that is E2EE.
While digging up supporting links, I was reminded that Element exists from the creators of the Matrix protocol, and while their website is an MBA-buzzword-athon their communities page does cite E2EE <https://element.io/communities#:~:text=secured%20with%20end-...> and they are permissively licensed https://github.com/orgs/element-hq/repositories
I mean there's lots of open source stuff. Signal is open source and people still complain about it being centralized but just won't run their own servers and connect them together. So I think open source isn't enough. It takes people working on things.