At one time 'Congress' represented the 'people' and their wishes. Now Congress is just an entity of government, more subservient to TPTB than those who elect them.
But still, if the majority of the people should conclude crytocurrency is a better deal than fiat notes based on debt, printed out of 'thin air', accountable and generated by a secret cabal, who is only somewhat accountable to the executive branch, then under the Constitution, it's whatever the people demand, given that they have the backbone and wherewithal to demand such.
And “digital currency” isn’t created out of thin air?
It seems way more insubstantial and less tied to “value” then what we have now. It will be far more vulnerable to manipulation both by “private hackers” and by “the people” via government demagoguery.
I know using the modifier “digital” in front of currency makes it all “cool” and so new millennium.