Fiat currencies are simply units of measure that governments require to pay taxes or transact their business. It is taxation that gives them value and allows them to be a store of that value. Death and taxes are, after all, the only two sure bets.

Crypto, like gold, will always be just a commodity. You know this because its value is expressed in the currencies of the countries it is traded in, not in itself. A dollar will always be worth a dollar, like an inch or centimeter will remain constant. When crypto's price takes wild swings it is simply being expressed in relation to a currency. In the end, like gold, crypto is useless until it is translated into a price related to a currency that other commodities are priced with.