The problem with federated alternatives to centralized services (and also one of the main problems with centralized services which lead people to look for an alternative) is Discovery.
Etsy and Twitch and YouTube provide an audience, supposedly. With the right pitch (and the right advertising dollars) you can get your own slice of that audience. (For as long as the algorithm graces you, and as long as you're willing to stomach the other things your viewers will be algorithmically suggested.)
