You already do use stablecoins, you use BankOfAmericaDollar (or WellsFargoDollar or...), which is fully convertible 1:1 to USD - some exceptions may apply. Your

You already do use stablecoins, you use BankOfAmericaDollar (or WellsFargoDollar or...), which is fully convertible 1:1 to USD - some exceptions may apply. Your BankOfAmericaDollar isn't backed by currency, it's backed by assets with variable values, and there's an insurance fund that may cover some of your deposits, again limits and exceptions may apply. Unless you have tender in your hands, or a fedwire account, you don't actually have 'real currency'.