dont agree, paper fiat are based on the promise that you will exchange it fro goods and services. The difference with gold and bitcoin is that you have a natural expectation of exchanging them for good and services in future based on their property and phisical laws;
with paper fiat the expectation is based on an artificial gun enforced centralized power that promise you to maintain power and dont fuck up all. And most of fiat promise are been already broken, all of them will be broken at some point.