In my quest for a #Discord alternative for my gaming group, I'm going to toss #Matrix into the bin of "nope". It ticks most of the boxes, but holy fucking hell the constant nagging to revalidate every fucking login is not going to fly. None of my friends are going to tolerate that shit just to talk about #TTRPG scheduling, campaign planning, and general life events. Intensely user-hostile.
@SharpCheddarGoblin I keep mentioning #Zulip to people, as I like how it organises things, but people may bounce off of the interface/experience. It's neither federated nor encrypted (besides usual TLS), which may or may not be a factor in your considerations. I saw mentions that they plan to have native video calls this year, instead of integration with e.g. jitsi like they do now.