Indeed moving away from toxic environments is an important point and should be encouraged and documented.
Then, how to build a non-toxic community is important, as are all the tools that will help (thinking about Elinor Ostrom institutional arrangements here, and The Art of Hosting Good Conversations Online by Howard Rheingold, that remains a classic). Indeed, Discourse provides a fantastic set of tools from building and managing communities, probably the best starting point we’ve ever known for online communities, but then as with every software, the way you use it is as important as what features it provides. Some old email, Usenet or IRC communities remain, not because of their tooling, but because of their institutional arrangements and the boundaries, rules, coping mechanisms and sanctions they have put in place over the years.