actually what he said make a sense,
but it will affect the entire economy ? i doubt that it will.
Bitcoin has not prove its usability wholly because there're a lot of problems that we will face when people starting to adopt it in their real life.
for example the transaction and the fees itself,
what make it so special compared to other is its usability,but if the hype continue while nothing change i believe it'll be bad for Bitcoin itself in the future.
also CME listing is a bad move for Bitcoin right now but at the same time,
it's the trigger for people to know about it.
everything is like double edge sword for Bitcoin,they have their own advantage and disadvantage.
I guess it was just a another rumors coming from those who didn't wan't bitcoin to succeed. In fact those countries started to adopt bitcoin didn't have any major issues about that said problems that may occur to fiat economy. Each currency has it's own specific negative and positive breakthrough in terms of usability and impact to society. If we have to review about Japan and Korea's bitcoin adoption, it went out smoothly without any reported cases of economic fall down. Now the understanding was of decentralized must always be in separate state compared to a centralized fiat cash currency.