It was unthinkable in 2020 that Tumblr would have #ActivityPub support on its roadmap. The quick shift in narrative, from a rehash of tech journalists going "it's too haaaard", to serious people giving it a try, then ordinary people.
My view back then was Mastodon probably wouldn't be The Thing. It would get us there, but would struggle to keep up. I'm starting to think Tumblr might be the thing. Automattic hasn't really been an EEE company, so I anticipate them being responsible players here.