Ponzis always have an exit. Fiat is no different, too many times happened already to say it's not possible for the Dollar.
I am sure after the BRICS meeting next month, gold or not, that a lot of countries are going to stop using dollars. Already agreements exist between numerous trading partners, India and Indonesia are using Rupees. Russia and China are using Renmibi.
It's probably significant that a former commonwealth nation is in the group. One that used to have one of the most trusted gold coins. The host, this year, even!
Just as gold isn't a terrible way to save your purchasing power, Bitcoin is also. Don't be sad it's not the legal one, that's how it works. It may have been all your life there was Legal Tender but that's a very new idea, not new in and of itself but to be so widespread is a fad of the 20th century, one that will die with the coming dedollarisation.