I agree that blockchain is yet another black swan much like the internet has been too. How to you propose that the blockchain be secured as it is absolutely dependent upon electricity, hardware, telecommunication platforms, corporations and governments to keep it running and available?

I'd say, just like the internet, blockchain tech is relatively immutable. Cryptobugs are notoriously the most conspiracy driven community, that is why they are firstly so passionate about the technology, and secondly early adopters in a wildly speculative and volatile market.

Off-The-Grid infrastructure for mining operations outside of government's notice, I believe, with no relevant evidence however, have been and will continue to be built. Infrastructure where the energy is generated and internet connectivity is completely sovereign.

There are solutions being built such that Bitcoins may be sent via fax through radio waves completely negating the need for many of the main infrastructure that we use to transact in cryptos right now. The added functionality and ease is more a luxury, the base use is still immutable.

it would still be devastating if they turn off the switch and watched everyone perish because we forgot to take care of the basics first - self sufficiency for all our basic physical needs. Any thoughts on these vulnerabilities?

My opinion on the matter is rather bleak. Those who are unprepared in such a scenario will either suffer enslavement or perish. It is as simple as that.

On the flip side, I do believe the community of preppers are growing at an exponential rate and that when the time comes, there will be many who will be prepared.