I think there's a bit of sleight of hand in this article.

Let's objectively consider whether cryptocurrencies really meet the 3-part definition-of-money test:

- Store of value: Not really - values are subject to wild gyrations and lack the stability and resiliency of the most important currencies they seek to substitute: USD, EUR, GPB, YEN.

- Unit of account: Not really - sure you can quote prices in cryptocurrency, but have another look at prices a month later and chances are they've changed. The real price quotation occurs in a stable currency that is simply convertible to cryptocurrency, the crypto-quotation itself is derivative.

- Medium of exchange: Not really - the number of merchants and service providers that accept payment in cryptos is still exceedingly small and very far from reaching anything near a critical mass.

Some of these points may be debatable, but I think it would be very difficult to seriously argue that cryptocurrencies, in their current form, meet all three conditions of the 3-part test. Therefore, by the author's own selected standard, cryptocurrencies fail to meet the definition of money.