If we are adopting crypto as a global currency, not everyone will be able to survive because the basic necessity to use crypto lies in the ability to use the internet. As of now, the literacy rate is not impressive especially when it comes to the technology and hence not everyone will be able to use cryptocurrencies to transfer the values. That would give big trouble for the entire economy.
Yeah, to using crypto it's need at least basic skill on computer and internet. It will be really annoying, because there are so much people on the world that didn't know computer even internet, even though technology has developed so far.