Everything cryptocurrency purports to solve has been “technically” solved, but it’ll become indispensable because of the elusive idea of post scarcity.
The perceived ownership of this message and the surrounding content (my blog) can be trivially duplicated a million times over at little to no cost by anyone.
I don’t care about that, but I guarantee you that a lot of other people do. Cryptocurrency brings scarcity to a post scarcity (digital) world. This is something that people desperately want.