People don't stick together. They have their sub-communities. One community is blocked, banned, destroyed, and the members can't just get back together easily. They make their own subcommunities which are progressively banned until they have to join unrelated communities where they think they've made a "compromise" of having people around them but not talking about the main issues they want.
Central leaders are important in these cases. People who will stick the majority together and push them toward an alternate community where they will survive.
Anyone can be a "central leader", as long as they know the best place to go and have the means to communicate and persuade the majority.
Many communities are broken up like this nowadays and it's sad to see it. The solution is to look around, find the dogmatic people and take the utmost measures to protect yourself.