There is a fundamental question as to whether a decentralized model is sustainable over time. What are the proper incentives? Does a carrot work better than a stick?
The BIS, an 88-year-old institution in Basel, Switzerland, that serves as a central bank for other central banks, said cryptocurrencies are too unstable, consume too much electricity, and are subject to too much manipulation and fraud to ever serve as bona fide mediums of exchange in the global economy. It cited the decentralized nature of cryptocurrencies — Bitcoin and its imitators are created, transacted, and accounted for on a distributed network of computers — as a fundamental flaw rather than a key strength.
The energy consumption question is one that is being raised more and more as Bitcoin itself becomes more mainstream and as transactional businesses, particularly those related to remittance slowly make their way to blockchain technologies.