I don't really care if fiat will fail wise investors don't hoard them because they hodl Bitcoin and other future proof assets. How can you be sure if those currencies will be gone forever OP? I understand that USD has undoubtedly dominated the world of currency but how long will it take to get us into the point of having only one currency as you said there are few players left so maybe you mean this is a competition.  Are you from the future as a time traveller? Do you have some hard evidence to come up with this idea? Please enlighten us so can prepare for something that might be on our disadvantage.