I've always used a harry potter community as the best example of a popular niche. It has millions of followers who love to read, write and create new content on the subject. So many theories, discussions and fan fics that get created by a group of followers.

They would not however be a crypto group so if we were to in theory build a community like that it would need to be very user friendly with the right tokenomics to thrive. I have often though about it if we had the tools for everybody to create and moderate specific communities like this, only tied to hive at a base and token layer as the users would never need to see or hear anything about the blockchain running underneath the community to enjoy it.