Honestly the best YouTube alternative at the moment is Nebula. The problem is that it's a closed system. You can't just make an account and start uploading, you have to be invited. So the range of content is fairly limited compared to YouTube. But unlike many other platforms, it is designed to be fairly general-purpose. There are some excellent individual creators' platforms, like Dropout, Viva+, Club TWiT, etc. But you only get a single creator/team's videos on those. Dropout is improv comedy. Viva+ is sketch comedy. Club TWiT is tech news. Whereas Nebula is more of a coop owned by tens of different creators with content including news, media analysis (including film, games, and music), politics, science, short films, game shows, and more. It's not federated, but it's independent and worker owned-ish.