Why does he even think like that in first place. It is the price difference and exchange capability of bitcoin and fiat currency which us making is rich. If that gets replaced with one currency then how we can get the profits or how we can differentiate ourselves with that price tag. I think it's not possible because it's just not well possible! There can not be two sun in the single solar system, it will burn the life. So there can not be two currency otherwise it will just break down the economy of country. The dollar bill is something related to traditions, old ways of trading and it will never get replaced in any time soon. Bitcoin is perfect fit in the internet world and might not just fit in the real world. So may be not this time.