Bitcoin does not exist outside of modern technology. It’s very existence relies on the internet. But the internet isn’t some nebulous thing that exists in a void outside of human economy. So there’s a fundamental cost in a currency other than bitcoin that must be paid in that other currency before the bitcoin transaction may take place. In the language of Econ, Bitcoins transaction costs include interacting with another (more broad) currency. The value of bitcoin then will, must always be dependent upon another currency. Hardly seems the Libertatian panacea that it’s made out to be.
As for Krugman and predictions, one never makes a prediction without a hearty dose of humility. Predictions are the playthings of fools. Believe me, he knows that. But predictions still produce clicks and views.
Edit-
One might liken bitcoins value through Greshams law (https://en.m.wikipedia.org/wiki/Gresham%27s_law ).
