That’s great but this does not account for the dynamics of a Discord server.
Let’s say 8 people are hanging out in Discord, playing games or whatever. Should I then message all 8 of them a link to join a separate voice chat? The response would be “no, just join Discord of you want to talk”. That also requires me to know who are in the call (therefore already using Discord anyways), since if I just message one or two of them I would be splitting the party, which they won’t do.
The whole “hanging out in Discord and whoever wants to join just joins” dynamic is difficult to replace with a zoom-type voice chat that requires you to initiate a call with a link.
I have already tried switching people to signal from Facebook messenger. Didn’t work. All it takes is one person to not want to switch and the whole group will end up going back. And that’s just a messaging service. Discord is way more complicated to switch from since it is more of an all-in-one thing.