Is There a Next Step for an Early Subculture to Build Momentum?

The long tail is the ability to reach increasingly narrow niches, and I don't really to build businesses and subcultures around them, but to almost create a beachhead for which to expand right Amazon starting off with books and then expanding to being the everything store. Would you see these niches starting to build, let's say something like a blockchain where in the beginning it's just a small subset of people who are able to congregate together on the internet? What do you see as that next step for an early subculture like that to start to get momentum?