I think that person was being very reductive when they said "making things up", the person they replied to was extrapolating a lot of things based on a faulty understanding of the crypto space, hacking groups and Russia.
Many people are not open to the concept of a working and legitimate aspect of the crypto world. Or "legitimate"/"use case" is something that people will play devil's advocate on forever ad nauseam, as opposed to learning or understanding why people are willing to keep building there (somebody will ask, name one legitimate thing, and then argue about why all the replies are not legitimate as opposed to how individuals are and could address various problems). So people get tired of talking to those kind of people.
Can you please name what these specific use cases/'legitimate things' are? I'd take literally 1 example. My experience (full disclosure of priors: I don't think they exist) is that crypto enthusiasts always vaguely reference them, and then when you look at it it's a tiny project used by virtually no one. I am unaware of any mass-market crypto product that's used by say millions of people, but you certainly prove me wrong by naming one or two.
As far as I can tell crypto is a place for speculation, ponzi schemes, and (to be fair) is a mild upgrade in the field of illegal payments. Other than that, there are no legitimate use cases 15 years after its invention. It's just a technological dead end with an unusual amount of hype
The most obvious way I can see a disconnect is that I view financial services as a legitimate use case, because outside of crypto it is a large industry already that exists solely because there are finances to service. Speculation to be made easier. Its the underpinning of the global economy as the largest industry and every service provider involved takes a tiny cut and is largely invisible. Every other industry and non-financial innovation is smaller and operating within this reality.
The same occurs in the crypto space.
What I mostly see are people that were fundamentally uncomfortable with speculation and serving speculation, and were either redirecting that energy towards the crypto space, or completely segregated from the financial services reality they live within. Unaware that their chosen criticisms applied equally to things they respected.
Okay, so one use case: the Uniswap application and its code base has over million users. You can look at this dashboard to see just Uniswap’s monthly users which seems to peak at 800,000
you can further extrapolate that to all the clones on Ethereum and other blockchains that have higher throughput
Uniswap’s “liquidity pool” concept solved a big need, while also introducing new problems that people rapidly try to improve upon.
Otherwise, crypto exchanges have been a large extortionate gatekeeper in commerce, and attracting liquidity even after being listed was a major challenge. The liquidity pool concept solved that.