It was useful but it was not understood to be useful by a large majority of people.
The crypto industry has developed novel crowdsourcing (ICOs, DAICOs, etc), fungible and non-fungible tokens, transparent voting mechanisms, token curated registries, oracles, prediction markets, state-channels, distributed time service, Zero Knowledge cryptography, leaderless consensus in distributed systems, fraud proofs, algorithmic stablecoins and a lot more.
We're also discussing whether it is actually useful or not, not whether it is widely understood to be (which depends on it being useful first). So the question remains, what utility do cryptocurrencies provide so far?
I have a feeling there will be a steady demand for this in the future, but I'm not sure how the bitcoin <-> fiat exchanges are going to avoid government attention.
What has the crypto industry actually done other than replicate some basic currency transfers through a highly inefficient and unintuitive trade of virtual points? It's a great research concept but it had no purpose in its creation, and finding some utility to bolt on top has so far proven to be futile in practicality and feasibility.