I'm biased, as I lead the Zulip project. But I think this is a reasonable place for me to post some thoughts. Given current events in the USA, I can't emphasize enough how worried one should be about the fact that a few companies like Discord, Google (Gmail), and Meta have databases with access to the private conversations of hundreds of millions of people with their closest friends and family members, linked up with…
I'm asking because I hate Matrix and actually want you to convince me: why should I accept the risk of migrating my friend group from Discord to Zulip, which has already "broken the seal" of restricting features behind a monthly fee even for self-hosted users, when I could migrate us to Matrix instead? Matrix seems like the much less risky option. I see that you have a "community" tier that's free and doesn't restric…
For the community tier, you don't have to do anything up to 10 users.
If your server has more than 10 users, you fill out a brief form (https://github.com/zulip/zulip/blob/main/templates/corporate...). We work hard to consistently process these requests within a couple business days, and the vast majority of communities are approved for full sponsorship without further interaction.
(Large communities managed by a business are quoted nonzero but extremely discounted pricing for self-hosted notifications).