@utopiArte Friendica or, better yet, (streams) or Hubzilla.
Friendica has been around since 2010. It's the oldest surviving Fediverse project. It even predates diaspora* by several months. It was created with the very intent of having an alternative to Facebook that's better than Facebook.
Hubzilla was created in 2015 from a 2012 Friendica fork, all by Friendica's own creator. So it's older than Mastodon, too.
(streams) is from 2021, the most technologically advanced of the bunch. It was created by the same guy who also made Friendica, Hubzilla and everything in-between, and who still maintains it.
There's also the (streams) fork Forte which is basically (streams) with a name, a brand identity and a license and without any support for the Nomad protocol, only using ActivityPub for everything. But I don't recommend it as long as it isn't officially declared stable.
"Unshittified, decentralized, and free" applies to all four. Friendica was relicensed by its new maintainers from the MIT license to the GNU Affero GPL in 2012. Hubzilla and Forte are still under the MIT license. And at least the core streams repository was intentionally released into the public domain.