Feudalism : The nobility held lands and means of production from the Crown in exchange for service, and vassals were in turn tenants of the nobles, while the peasants (villeins or serfs) were obliged to live on their lord's offices, factories and give him homage and labour, in exchange for protection.

If the people running these things are doomers, there's no need for capitalism to work beyond what it takes them to build their compounds and bunkers right now.

And since a large number of them seem to be building compounds and bunkers...

Capitalism can only sort of work when there is balance between the classes. Inevitably, one wins over the other, which leads to fascism or communism, and later a big reset. If the proletariat (i.e. those who depend on a salary to survive) aren't able to sell their work anymore, the owner class won't need them anymore. I personally see three outcomes:

* Apocalyptic but unlikely: the bourgeoisie gets rid of the proletariat and goes on to enjoy boundless luxury.

* Awful but likely: the bourgeoisie throws just enough to the proletariat that they won't rebel, and goes on to enjoy boundless luxury.

* Utopic: the machines' output is democratically decided and evenly distributed among the entire human population.

Keep in mind that the scenario in which machines are able to replace all human labor is still very remote, and won't happen suddenly. I'm sure many things will occur between now and then that will completely invalidate my simplistic predictions.