as a person that came from the 3rd world country and new in fediverse environment, i genuinely would like to know about this.
edit: thanks for the replies! sorry, i literally don't know the reason since i'm not a western lol. twitter/x is too biased especially when musk openly supports trump so i came here and seeing fediverse is mostly are harris or biden (when he's still up for the candidate) supporters. don't know about reddit tho, i only use reddit as a forum for linux and programming stuff.
The preppers are different because they want to be left completely alone. They don't see any acceptable role for government in their lives. I don't think they're being realistic. Freedom isn't free, as the saying goes.
The techno-libertarians are much more engaged with society and do see a role for government, even if that role is small and (at least according to some of them) bizarre by conventional standards. I'm not going to deny that the bunker-building types are involved in the movement. I often don't agree with the weirder people involved, but I like that techno-libertarians are willing to hear people out and judge their ideas rationally rather than shunning them for being weird.
(I think I might have a bunker built if I was rich enough. The expected utility of it is higher than that of, say, a second yacht. Human guards are a dead end. Probably the best thing that can be done if civilization totally collapses and you manage to get inside is blowing up the entrance so that anyone who wants to get to you has to move a thousand tons of rock first. You probably won't ever get to leave, but it's better than what would happen if you did.)