i actually think blockchain tech will come into mainstream use much more quickly. the average joe doesnt need to understand it to utilize it. i see it operating behind the scenes in ways that most of the end users wont be aware of
For now the average joe doesn't really have anything that's easier to use than cash or credit card.
its possible that the first mainstream utilization of blockchain tech will not be as a pure crypto currency but more of something that runs in the background of a web app or platform. i think projects like swarm fund have a real shot at seeing mainstream adoption in the near future