It depends if you want to use it like Twitter (public announcements) or like Facebook (closed small/medium circles). If you use like Facebook, then it's enough that one person among your circle of friends (probably the most tech-savvy one) would host a pub and use that for their friends. You can see how you would probably be connected to a few pubs, because you usually have different circles of friends. If you want to use it like Twitter, then indeed we might need a DHT, but the point there was the resilience of the network.
Okay... in the FB case, though, my friend has to send me the IP/DNS address of their pub somehow, right? eg; Signal?
What about organizing groups, which might currently use Slack? For example, political dissidents who don't necessarily all know each other personally. They must use some other communication channel to communicate pubs?
