When I checked mattermost a year ago, the mattermost opensource edition had no basic permissions/access control. Any user could archive any channel. I have seen many teams fall into this "trap" only to find this basic restriction later. We since moved to Rocket.Chat. Is this still the case?
Keybase is.. not ready for prime time. It's pretty janky, channel discovery is a pain as is spam, and it's still got that weird crypto half-baked nonsense.
Access control is intentionally missing from the open source "team" version:
> Team Edition is "virtual office" where a team works together as trusted colleagues. It means people can walk anywhere they want, and move the furniture if they choose.
> I need to ask this ticket be closed since it's not a bug
> You're of course more than welcome to fork as well.
But would Mattermost accept a PR that cuts into the differentiation on "advanced access control" of their enterprise product? https://mattermost.com/pricing/
Open source is only as powerful as the community's willingness to maintain a fork.