This reminds me of --

- Networks of "safe spaces" marked by rainbow flags or triangle icons.

- The vision of WeWork, before it imploded.

- White-nationalist and right-libertarian groups who invest in militias and firearms.

- Black separatist movements, like the (peaceful) one happening in Freedom, Georgia: https://thefreedomgeorgiainitiative.com/

- CHAZ and other "autonomous zones".

- British Zionism before the existence of Israel.

- Other nationalist movements, like Irish Republicanism. See also the IRA.

- Charter Cities: https://www.chartercitiesinstitute.org/

- The creation of new subreddits. Opaque and off-putting vocabulary, like WSB's.

- The Amish system of communal aid and health care.

- American utopian communities, like the Oneida community.

- The Islamic State, and its publication Dabiq.

- 70s-90s subcultures, e.g. hippies and punks.

- The Mormon Church.

A number of properties seem useful:

- Barriers to entry. E.g. a language (resurrect a dead one, like Gaelic or Hebrew, as done by previous nationalist movements? Or Arabic, as was encouraged by Dabiq? I see possibilities for indigenous languages (e.g. there is a fringe neo-Aztec movement), for Latin, for Sanskrit, and for a reverse-engineered PIE).

- A coordinating media apparatus (again, Dabiq is a good example).

- Risk-pooling with defenses against free-riding (see the Amish).

- Significant exclusive advantages to members. (The Roman system of earned citizenship is one example.)

- A strong reproductive capacity, whether purely memetic (LGBTQ movement), or biological. In the latter case it's vital that the ideology minimize within-group gender conflict (ideally without domination), and assist productive heterosexual union. Consider the symbol of the upturned triangle (male) and downturned triangle (female) interpenetrating to form a union with new symmetries; in some cultures this is the "Star of David", but it is also known outside those cultures. This might be achieved through separate (but interacting) male and female aspects of the culture, instead of through a completely unisex culture. It needs to achieve r > 2.1 or it's dead in the water.

- Mechanisms of self-defense, ranging from passive denial of benefits (blacklisting), to coordinated harassment (Twitter), to limited and mostly symbolic violence (parades, protests, street riots), to real organized violence (militias). It's a good sign if people are afraid to criticize symbols of your tribe (see Charlie Hebdo). Though insularity, stealth, and non-aggression -- a purely defensive strategy -- might get you reasonably far if you can quietly obtain resources.

- A moral narrative about the inherent goodness and righteousness of your people and your cause. The weakest would be a pluralistic "we have a right to exist too"; the strongest is "we are morally superior" -- whether because you are the "Master Race", or "chosen by God", or those most downtrodden and deserving of justice, or those with the best principle ("liberty"). But the first step of war is always demoralization of the enemy, so you can't neglect this. Fake corporate values don't work. Cynically, the moral case has to be a stealth restatement of the interests of the group members.

- An immune system capable of dealing with agent provocateurs, whether by embracing them ("Nothing is too radical!"), or by ejecting those who violate some more nuanced concept of "good".

- A founding myth. Ideally a true one.

- Heroes.