holding can also be considered as failing, if we think back so called cryptocurrency was envisioned as a replacement for fiat currency but soon it lost its path and became a substitute of gold and other assets. nobody is gonna give bitcoin for a cup of coffee just like gold.
untill unless a cryptocurrency is created which community supports by exchanging their goods and sevices for it, afterall the beauty of fiat currency lies in spending it not holding it. so far cryptocurrencies have no community backing, nobody is liable to accept and no intrinsic use of the currency itself apart from being an instrument of speculation just like stocks on which large fund managers play a bull and beer game called trading.
that being said about cryptocurrencies, Blockchain was the idea that has seen the success so far and provided us with numerous decentralized solutions like steemit, etherium and much more. these plateform and their cryptoassets have backing of their community unlike plain cryptocurrencies.
According to me the blockchain has proven itself but cryptocurrencies have still a lot to achieve in order to be termed successful.
True, that's a very good point and the route I should've taken.
Either way, most of what we see today won't be here in 5 years. But like you said, Blockchain tech will 100% be.