I've also have been using Discord for voice almost daily for a little over a year and it just works 99% of the time. Unfortunately, it suffers from "gamer" branding that makes it awkward suggesting for work. They should try offering a "business skin" that interops with discord.
It's just a means of communicating, people. Maybe a few Discord features aren't useful outside of gaming and a few Slack features aren't useful outside of the workplace. I find that to be a stupid reason not to generalize the use of these products. Skinning (and filtering away those specific features) just might be the ticket.
Mind you, I only host it at home on a VM for personal use. Have had sessions with 6 people with one of them a Europe-Australia connection. All fine on default 720p.
If I were looking for 20+ meeting software though I'd consider something else. I would consider it a case for streaming to faceless attendees. I have never had a meeting with useful input from more than 10 people.
The company my wife works for can't get a reliable Teams conference going with anyone in France.
The company lied about their encryption.
Both of these statements can be true, it's just a question of trade offs.
I know they just announced their own "Ring central video" But im weary of that for the time being.
Separately: affordable servers likely are accessible to infrastructure providers (whether a VPS, or bare metal at a colo, etc.) so it's tough to say that "my own server" is usable exclusively by me and therefore not adversarial. Plus, maybe people want to use my server and consider me adversarial for whatever reason; they should use their own server instead, but might not have the skills.
It's in here somewhere: https://jitsi.org/security/