We would like GitHub integration, strong spam/moderation features, and avoid the hassle of self-hosting. gitter.im used to provide those, but they were lost in the Matrix switch.
Some example Matrix communities which seem to work well include Mozilla (chat.mozilla.org), GNOME (https://matrix.to/#/#community:gnome.org) and KDE (https://webchat.kde.org/). Smaller ones include folks like Helix editor: https://matrix.to/#/#helix-community:matrix.org. I don't think anyone's written a guide for getting up and running though, which in retrospect is a crying shame; we'll get it on the todo list.
(p.s. thanks for Hex Fiend! :D)
Well, yes and no. The moderation features might be the same, but:
1. It's a lot easier to make matrix accounts, especially if you run your own server.
2. The user interface for blocking an entire server is basically missing? The only thing I can find has you run a bot to do it?
So if someone with their own homeserver wants to troll you, you end up playing wack-a-mole unless you self-host a bot. At least that's the best I can find so far.
I don't know how well the public Github bots will work for your use case. The moderation tools are also relatively crude in my experience; at the protocol level reports/ACLs/reporting is quite easy to use, but there's no easy Matrix moderator frontend that I know of. There's a bot (mjolnir) but not a separate UI.
You can pay people to host your Matrix server or you can use the public home servers to set up your community/spaces. Self hosting usually isn't necessary.
I set up Maubot for GitHub integration: https://github.com/maubot/github. There are moderation features, but we haven't had to use them.