Comment by ktpsns

I just gave Zulip a try with a team of 3. I loved the UI because I spent years in pain finding things in big Slack and Mattermost installations (big = 30 users, nowhere near enterprise-level). For my two junior colleagues, instead, Zulip was too complicated. We evventually switched over to Discord.

I highly recommend Zulip to anybody who faces the problem that the concept of threads and channels is not a good fit to their mental model of tasks and groups in teams.