Cryptocurrencies have proven that we Can transact anonymously without a centralized interference.
The Blockchain has proven that data can be stored in a decentralized public ledger against any form of manipulation.
Smart contracts has proven that two or more people can trust a system in which the assigned contract managing it will be fair to all parties...

When speed, simplicity and efficiency is added to all of this I think decentralization and blockchain technology can go far in the real world as regards adoption.

What do you think of the chances of cryptocurrencies to succeed?.