It’s a social graph that’s divided by time zone.

I can’t be connected to these people because I live in Europe and so times when I can reasonably be on a phone call do not overlap with theirs.

Twitter on the other hand... I can be connected with these people and not only can I “catch up” later, but reading Twitter in bed is more socially acceptable than being on a conference call.

It’s strange to me that both you and I are getting downvoted… probably from people who haven’t actually used it? If you do, then it’s obvious how it’s not a conference call at all. It’s a panel that you might be able to participate in, which isn’t the same thing at all. Anyone can talk whenever they want on a conference call. The moderator chooses who talks in clubhouse.

Conference calls have had guest management and moderation features for decades. Also several dozen social platforms already support livestreams with more functionality like video, files, chat, etc.

There is conference call software that only allows a panel to talk. It's used to give remote presentations to a large group of people.

For example Webex has a product for that, as well as Bluejeans.