Apart from illegal activities (drug dealing, Ransomware payments), I have not yet heard of a true use case for Crypto currency. I can potentially see it's use by speculators, betting on it going up and down. But that's not really a proper use case, that's just betting by a$$hats.
Like so many commodities, you only really have the "value" of the product once you've sold it for proper goods and services (or another intermediate currency with which you can buy actual goods and services). So, whilst Kim might be sitting on a ton of Crypto until he can shift it to cash, or find some other way to swap it for tangible goods, he's not really getting a benefit.
What I would like to see (but it's not going to happen), is for Banks and other financial institutions to be prevented from dealing with Crypto, and perhaps punished for providing crypto for the purposes of paying ransomware. If the firms cant buy crypto from legitimate sources to pay the ransomware scum, then the whole ransomware economy dies. And very few firms would be willing to go to a dodgy or sanctioned provider to get their Crypto, as the fines (and risks of losses) for that would be far more than what the ransomware costs would be.
The whole point of any currency (legitimate or crypto) is to be able to exchange it for goods and services, being left with a big bag of Zimbabwean Dollars is not going to get you anything. Just like being stuck with a big pile of crypto, if no one is willing to give you anything real for it...