On the Fireside Fedi interview with Jerry ( the admin of Infosec.Exchange Mastodon instance ) a scary truth was suddenly revealed ( on 34:11 ): Just to keep the instance up and running he needs to spend up to $5000 a month, pretty much out of his pocket. Donations to the instance barely cover any of that. And if he will ask people to pay to use it, they will, rightfully so, switch to a different instance.
It is not a matter of efficiency, but solely of how AP works. All it takes is someone one an server to to follow a community for that server to receive every vote/post/comment, while to get a whole conversation thread on Mastodon you’d need to be on the same server as the original poster or your server would need to have at least one person following every server involved in the conversation.
Thanks, that makes sense if I think about it, but maybe users shouldn’t have to - i.e. the Mdon part-conversation way still seems confusing to me (despite being a climate modeler and scala dev), although haven’t used Mdon much since I found Lemmy. And I still feel that both ways seem intrinsically inefficient - for different reasons - if we intend to scale up the global numbers (relating OP).