@taylorlorenz I've actually though of how to describe Mastodon in a short way to non techi-people, while keeping in mind what prevented me to join any federated network before.
The whole point of Mastodon is to put back controls of their social networks to the users. That means it's not design around advertisements and unknown way to select content for you. Instead people run servers around given thematics. There is no need to have algorithms which choose for you content you might be interrested for, instead you find a server which have a community around the same interrests or localisation, and your local timeline will be filled of content from people of the same server, which have the same interrests.
But as it's federated, nothing prevent you to read content from other users. Because an account creation is easy, you can also have alt-accounts to discover other communities, and follow people from there on you main account. Most of the Mastodon apps can manage multiple accounts.