100% agree with what Financial Stability Oversight Board has written.
300-400K transaction/day are not more than 0,1-0,2% of all transactions made in the world.
And 600 Billion $ market cap is nothing if compared with all financial economy. More info and comparisons here:
http://money.visualcapitalist.com/worlds-money-markets-one-visualization-2017/
Still really, really small!
“Virtual currencies are only used by a very small number of consumers. We give a bit more credit to the potentially much broader applications of the so-called distributed ledger technology underpinning the innovations. It is noteworthy that this digital wave also presents a regulatory challenge, because the storage of data is decentralized, rather than being in one spot that governments can watch.”