I think in order for an open source federated social media to really take off, a notable company needs to adopt and host it. I've seen it happens at least once and it happened quite recently too. I'm talking about Pixiv, the Japanese equivalent of DeviantArt (but focused on anime/manga artworks, no photos allowed) who is hosting a Mastodon instance and named it Pawoo. It is widely used by Pixiv artists as it is seen as a complementary service to Pixiv network. I'd love to see Pixiv adopting and hosting a Hubzilla instance too.
https://pawoo.net/
