I'm a blockchain sceptic but I think this is too harsh. The arguments are mostly taken from Bruce Schneier's (better) article, available here: https://www.schne

I'm a blockchain sceptic but I think this is too harsh. The arguments are mostly taken from Bruce Schneier's (better) article, available here: https://www.schneier.com/blog/archives/2019/02/blockchain_and_.html https://www.schneier.com/blog/archives/2019/02/blockchain_an.... There, he says: > Honestly, cryptocurrencies are useless. They’re only used by speculators looking for quick riches, people who don’t like government-backed currencies, and criminals who want a black-market way to exchange money. and he points out that many forms of trust provided by e.g. credit cards or currencies are non-technical and not solved by blockchain. For example, they allow you to cancel a transaction you made by mistake, or to prevent someone stealing your card. This is fair, but note: (1) we use cash, and sensible people don't want to abolish cash, even though it has the same problems as bitcoin (e.g., if you lose your wallet, you lose your money; someone can steal it from you) (2) services can be layered upon bitcoin, just as they can be layered upon cash. For example, if someone steals your cash, you can go to the police. And if someone steals your bitcoin, you can go to the police. (I appreciate that if "someone" is in Russia, you're out of luck as of 2022.) Similarly, an honest retailer will refund your cash for a mistaken transaction, and they could do the same for bitcoin. (3) The set of "people who don’t like government-backed currencies" is quite large, and it is not limited to libertarian ideologues. Especially, many people in developing countries would like their savings to be safe from government-caused inflation and/or from "financial repression" where interest rates are kept artificially low to support favoured borrowers. This suggests that cryptocurrency has at least one valid use: an alternative to gold. I don't know if there are any others.