Why Discord though? Truly independent project, keep big corps away, future of the web at stake here yada yada yet using the most walled garden of walled gardens. If there is no publicly accessible and searchable archive then might as well not exist.
Zulip. Open source, self-hostable, looks decent and not only does it have every feature that discord has, their version of threads/topics to spin off individual conversations is extremely well done.
And, don't overlook the indexability of Zulip so that information doesn't instantly /dev/null just because Discord hates having bots or because one can only ever(!) join 100 Discord servers
WAT? Not even close to true. A lot of people gravitate to other discussion forums. Some even dislike chat-style "communities" that they steer clear. (Someone can find market research if we want to pin it down more.)
My summary (exaggerated for effect): Discord is a time waster. Slack is Stockholm Syndrome. GitHub Issues is comfortable. Zulip is lesser-known but great and FOSS.
So many of these products have redefined our frame of mind for how we interact, for better or (let's be frank) worse.
SerenityOS used IRC but when Andreas changed to discord he saw a massive influx of developers. I assume that it was a no brainer to use discord when forking Ladybird...