I hate mailing lists, even if I recognize some of their benefits. A forum like Discourse is infinitely better in usability - to view, browse, search, follow specific threads or forums and mute the rest, do DMs, do real nested replies, embed rich media and code with proper formatting and just have a nice interface to work with. It looks like they even support ActivityPub federation recently. Although its GPL not MIT. I'm sure someone will come and tell me how all of this is doable with some janky interface or hacks on mailing lists. It's just unfortunate we have to choose. The people on mailing lists often argue vigorously for them, the rest of us are on discord/slack and have no idea they even exist and are repulsed by the usability problems. You can't convince me pasting diffs in an email thread is on par with Github/Gitlab code reviews with no downsides whatsoever.

the UI/UX of discord is definitely nice, but the /ethics/ of discord isn't.

I hate Discourse because I can't read it with a local email client.

I hate the look of Discourse, it looks like the worst case of a phone app and ""modern"" web design

I think it's primarily due to absence of margins on the sides and thin borders