Yeah i thinks its more likely even that bitcoin would be extinguished before fiat ever could be. The fact that fiat is controlled by governments and big banks pretty much assures us that no other currency now or probably in the future could challenge fiat's supremacy
Lol let me get this straight.. the fact that some people who call themselves "governments" or "banks" also claim to have some modicum of control over the issuance of a no-cost private issued note -- is an assurance that nothing will challenge it? By the same logic, I claim to control all snails. Therefore nobody will be faster than a snail.