Cryptocurrency technology has utility which has not been fully exploited yet. At present, the two variants with the most market cap, Bitcoin and Ethereum, do ha

Cryptocurrency technology has utility which has not been fully exploited yet. At present, the two variants with the most market cap, Bitcoin and Ethereum, do have reasons to exist. (Which, again, involves some present utility but more future utility.) Bitcoin has earned a certain degree of trust that value moved into that form will continue to exist, just because there is so much distributed hardware behind it that it would be hard for a bad actor to compromise it. It's not impossible, but there is a certain amount of utility there. Ethereum also has earned a certain amount of trust which, today, is based on hardware, but within the next year will be based on Proof of Stake, with many billions of dollars in stake. (The amount of trust it will receive will depend on how decentralized the stakers turn out to be.) But it also has "smart contract" capabilities. It has speed and expense limitations but those will be lessened over time with sharding, rollups, etc. There are newer crypto technologies that may overtake those leaders in market cap, or may not. In any case, there is utility to these technologies. Because of that utility, some portion of the world's currency supply should be in the form of cryptos in order for the world to get maximum benefit. Say that is X% for a particular cryptocurrency. (Remember, BTC and ETH have somewhat different roles and so may be able to coexist.) Then the value of a coin should be X * .01 * (the total value of the world economy) / (the number of coins). That's not a Ponzi scheme at all. What is happening is that the world is moving slowly, in fits and starts, toward the discovery of the numerical value X for each coin. On the other hand, DOGE really does not provide utility that isn't being provided by more trustable cryptocurrencies, i.e. others are more likely to stick around for the long haul without crashes making the coin asymptotically approach zero in value. So, it really doesn't have the same kind of reason to exist. It's more like the Dutch tulip craze. It doesn't seem to fit the technical definition of "Ponzi scheme," but that label does capture the fact that its price is only what it is because of previous buyers. [Update: edited to point out more explicitly that a lot of the utility is future utility. I say a little more about that in a thread below.]