squirrel

It’s been there for a couple of years. Found a GitHub comment by Gargron talking about what it is in 2022

The explore tab is in essence a moderated, quality-filtered federated timeline. Its purpose is to help you discover other people and expand your visibility, but without being a vector for spam and abuse.

Mastodon has an algorithm in their official app. The Explore feed shows you posts that are popular among people you follow and interact with.

Loops has a For You Page algorithm.

There are algorithms on the fediverse. They are rare, but they do exist.