Cryptocurrency is really a pure currency, that does not have any redeemable value other than as medium of exchange.
- Intrinsic value of currency = wealth of the economy with currency - wealth of the economy without currency
- Wealth of the economy = present value of GDPs for all future years
- Imagine how much GDP will decrease if we suddenly cannot use currency and have to barter for all buying and selling of goods and services.
Another way to look at this.
- Imagine only you are banned from using currency.
- You need to buy a TV. Your mind is busy thinking how to do this by bartering.
- A government officer comes to you and ask, "how much would you pay more for the guitar, if I allow you to use currency?"
- How much more are you willing to pay?
For a longer explanation, please read this.
FYI, my guess is that GDP will go down at least 20%. And I would be willing to pay 20% or more.