@darius Seems unlikely tbh. In 2009 Twitter had about 35 million DAU, so somewhere between 3-5x the current mastodon traffic. We know from this period Twitter was a relatively standard Rails app that looks like the attached image from their slide deck.

Since the Fediverse burns a ton of network traffic on communication between servers over the public internet (vs a local network inside of a single datacenter or two datacenters with an MPLS or fiber between them) and every Mastodon server needs kind of a lot of resources to just start and host one user, my guess is you could run a centralized Mastodon for 10 million users and consume a tiny fraction of the electricity the current system does.

Scaling a system up from 1000 users to 5000 users or 500,000 users is a small amount of resources vs adding 50 servers hosting 10,000 users. There are perks to the Fediverse but energy efficiency ain’t it.