The externalities of cryptocurrencies include:
Massive carbon emissions. Funding "rogue states" such as North Korea and Iran. Tax evasion. Laundering the proceeds of crime, including the drug trade, theft and fraud, and armed robbery. An epidemic of ransomware. A wave of securities fraud targeting the greedy and vulnerable. Shortages of products including graphics cards, hard disks, and chips in general as limited fab capacity is diverted to mining ASICS. Abuse of free tiers of Web services. Noise pollution.