One might answer your point about "not sure where you're going" by pointing to a lot of subcultures which are slowly dying out because they're not attracting enough new people to replace the slow dropoff to inactivity of the older people. They never quite go away but they drop below the threshold to have viable social spaces.
This would probably also be true in a better non-capitalist world! Society changes and people move on from things. Even in an ideal anarchist society the kids will still want to invent new stuff that their parents aren't into.
My experience is that a thriving growing group is one that's being constantly flooded by new people, and a healthy group is one that does that while retaining existing people, both by preventing burnout and by removing missing steps and abusers. A non-thriving group doesn't have as many new people coming in, which paradoxically means that the average experience of its members rises and they get better at the thing that they do.
I think this is where a lot of the superiority complex comes from: "we unicyclists are far better at unicycling than the aerials people are at aerials, why is it that our spaces aren't doing well and theirs are?" This in turn leads to policing and hypervigilance and many other shitty behaviours that make it even worse.
But of course capitalism complicates this by treating every subculture both as a market to be sold to and also as a product that can be sold to others.
Is that where you were going?