We are generally so habituated to services that plunder our contact lists and auto-populate our social graph that we end up all dazed and confused when checking out privacy-respecting social networks. Like … where are my friends at?

In the fediverse, you can choose your community, you have choices. Most servers (instances) gather around a topic, common interest or subculture and have their own rules and etiquette. An easy place to get started is https://joinmastodon.org/communities. If you discover people who "live" on other instances, you can still follow them.

It might take more time to build your social graph in the fediverse than on the centralized and commercial services, but the satisfaction of having a feed that you put together yourself, without being influenced by nagging recommendation algorithms is worth it – at least to me!

EDIT: To answer your question more directly, I'll add some of the people and projects that I find interesting and follow (and that you probably won't find on other social networks). YMMV:

- https://mastodon.social/@mntmn (researcher building an open source laptop, amongst other things)

- https://social.coop/@compost (a magazine about the digital commonts)

- https://mastodon.art/@BenjaminBrinckmann (talented painter / artist)

- https://indieweb.social/@bonfire (a project building a system for easier self-hosting of federated services)

- https://chaos.social/@delta (Instant Email Messaging App)

- https://fosstodon.org/@flockingbird (Federated version of LinkedIn in the making)

- https://floss.social/@forgefed (Vocabulary and protocol for federation of project and repository hosting)

- https://mastodon.social/@zrythm (young DAW software project)

- https://chaos.social/@ConnyDuck (Creator of Tusky, now banned from Google Play Store)

- https://linuxrocks.online/@dnkl (Developer making the great terminal emulator "foot")