As straightforward as mastodon is to setup currently on a server, my hope is that future versions are so very simple, and include plenty of automation, that even non-techies could setup and operate their single-user instance. Basically like installing SIMPLE software on a conventional desktop. And, that's not a simple task...but if/when that's done, then the barrier to entry and use will be low enough to allow for floods of users - arriving on their own single-user instance/server - to join the network.

So, for now, yeah it takes a little work in setting up your own single-user instance, but as another person posted already, mastodon supports that mode. Like all homesteading, it takes a little elbow grease. ;-) Cheers!