It’s actually not that hard. (Well it is, media and networking are hard, but)
I think the problem is that when people search for something better than Teams (or any other software), the confuse “better with”, with a mostly nonexistent “best”. In doing so, they skip over the way every single thing people suggest is “good enough”.
Like, following this thread, we went from “I want a teams (voice/video/chat) alternative” to “Yeah I don’t like Jami because it leaks metadata.” How did we go from wanting a teams alternative, to wanting privacy with no metadata leakage? Those are very different things, and you make tradeoffs if you take one set of feature over the other. If you just add “no metadata leakage” on top of your current wishes, then you are probably going to be disatisfied with every option given.
Or “Firewalls and hole punching!” (implying a p2p architecture) and “depends on peers being reliable” (being frustrated with the pitfalls of a p2p architecture). Again, wtf? Of course there is software that is half p2p and half client server, but that is hard and tradeoffs will end up being made, even purely in what the developer spends their limited time on.
This person just needs to get out of their head, whip up deployments for every software (or suite if there is more than one) mentioned in the thread, and pick the one that looks the nicest.
I already made a comment but you should also look at rocketchat and revolt, since they are basically FOSS discord clones
(I saw comments in the thread about wanting audio only calls.)