One thing I really wish #jabber app like #Conversations could do is ephemeral small group chats. The sort of thing where you just want to make one-off arrangements with a few people, or have a quick check-in to get on the same page, but you know you won't need to group chat for long enough to make it worth setting up a #MUC room. The fediverse can be useful for this, and Wire's group chat is better for this than ongoing team chat IMHO.