Well it's mostly scams like the first anon says.
Success of defying government power never comes in the form of some rich guy passion project, it can be pretty ugly. For example, the amish don't pay taxes and don't have to do a lot things americans have to but they are pacifists and don't use modern tech. Multiple mexican villages removed both the cartels and the government from their homeland, but they pay in blood by having the young serve in a private militia. South america in general has this thing going on with cartels being so powerful that the state can't tax regulate or even intervene in some regions, people even report that they rather pay some local gangster than the politicians, but having some cartel act as the government is not ideal. All you have to do is ignore the state and it disappears, due to resources limitations they can barely arrest /murder 2-4% of the population of a given nation and could not even make 10% economically crippled(turns out if don't pay taxes you'll have more money). They can't also waco everybody both due to logistics and resources, the american feds are incredibly well funded even for a first world nation, we don't see wacos everyday despite all the reports of "ghost people"(no documents), even globohomo admits there are millions in the us alone(like the family of that treacherous woman that wrote Educated).
I really believe religious group with more than 200k followers would be able to set up an ancap colony no problem. Conclusion: