It has been my feeling that any community, not just DU, but even my friends (Buddhist group) should have very local discussion groups, with calendaring and scheduling and structured discussions, of only HIGHLY TRUSTED members, with the ability to connect (somehow) to other similar groups.
As it is, we have some online discussions, but nothing is saved for future quotes (meaning lost) or to gather info into a knowledge base. That would be especially useful for new members, so they can catch up with accumulated wisdom in addition to getting current advice and hearing stories from leaders and old-timers that can be really valuable.
I am unfamiliar with all the recent forum software, and what I knew has changed names, just to confuse everyone.
In addition, I have some paradigms for information management not yet unleashed on the world. (top hush for now).
I have followed Moodle for many years, and it hasn't changed its name! YMMV, but I used to install it on laptops (my own) and company servers to hold my project documentation. Given that unless people do a deep dive, like using github, that usually amounts to going over someone else's "doc" files. Hardy collaborative.
So, I'll check into things "that just work" and as an aside, continue to urge people to use Signal Messenger. It messages, it does video conferencing ... and is designed from the start to be secure (though lazy use could weaken it in action)
No forum software that I know of is ultra-secure, but being able to move a small instance around (with those connections as needed) saves the "all your eggs in one basket" kind of vulnerability we see.
I do see more decentralization as big organizations cower to the emperor. (as in programs moving off TV, which BTW, I don't use except for one football game a week)