Well, before I never thought about the future of fiat currencies that might become obsolete. But, until I found an article entitled:

"Fiat Currency Will Be Laughable in Five Years Says Billionaire Team Draper"

Link: https://cointelegraph.com/news/fiat-currency-will-be-laughable-in-five-years-says-billionaire-tim-draper

In the article, Draper explains how fiat has limitations, the same limitations that really begin to interfere with the progressive and advanced thinking global population.

And I agree with Tim Draper's statement.