I think #mastodon is slowly getting mainstream.
Proof: the #kikk19 festival is the first event I've attended, which does not focus on alternative solutions, open source nor decentralization, though generally focuses on art, design and tech, where other attendees where posting things about the festival on the #fediverse using the official hashtag.
It wasn't a huge crowd, but still. A good surprise from my point of view.
@judeswae That's amazing