Also scans all chat channels for AI training...by default. This can only be turned off by emailing Slack customer service. Even then you are tursting that they actually stop.
Discussion
Slack is a gigantic feature set to replicate. Anyone who does it on Nostr should come up with a funding model.
Maybe private groups get a hosted private relay, and groups can pay for that hosting service.
Otherwise groups use shared relays, and there's no guarantee of privacy unless all messages are encrypted like DMs.
Slack was a mistake and should not be replicated. We need nostr irc. It's perfect because there both have relay right in the name.