Earlier quoted context omitted.
That's what ends up happening when an asset becomes economically meaningful. Crypto is still a joke to global economy, but on the off chance it gains mainstream adoption, it'll have the same kind of regulations, taxation and fraud attached to it.
Except crypto is less firmly anchored in the real world than in the digital realm. It's fundamentally harder to regulate it than a physical currency, which needs specialist equipment to generate.
As long as you can use something - be it a coin, a bill, a SWIFT transfer, a blockchain transaction or a Nuka-Cola bottle cap - to pay someone for something, and a third party would be able to identify it as a purchase, same things will happen. A criminal will be able to take your purchasing power and use it themselves. A taxman will be able to collect a percentage of your trade, and men with guns will take you in front of a judge if you refuse.
The manifestation of value doesn't matter, because money isn't a thing, it's a shared belief.