A community without a boundary either evaporates, or it attracts the social climbers and it becomes increasingly performative, transactional, and kayfabe.
This happens to every community that can go viral... even if there's no direct profit motive, there's an indirect profit motive to every interesting assemblage of people.
People who view but do not participate in a community are free-riders.
They get the value of the community but they don't have to contribute, and also make the stakes of experimentation in the community higher.
A key question for a community: the degree of overlap of creators and audience.
If they are highly overlapping, then the context will be a more infinite mindset, more authentic, more creative.
If they are non overlapping (the vast majority of participants are audience, not creator) then the more finite, performative, and transactional it will be.