When the power goes out or the internet goes down, how will you get to your bitcoins. And when the arrests start for tax evasion because they didn't claim their bitcoin (all cryptos) holding, the tax collector will get very rich and bitcoin holder very poor in jail. And then there is this: Bitcoin mining is extremely energy intensive. A single transaction of bitcoin has the same carbon footprint as 680,000 Visa transactions or 51,210 hours of watching YouTube, according to the Cambridge Bitcoin Electricity Consumption Index. The Oak Ridge Institute in Ohio found that a dollar’s worth of bitcoin took 17 megajoules of energy, that’s more than double the amount of energy it took to mine a dollar’s worth of copper, gold and platinum. That poses serious ethical questions for corporations and governments looking to curb their own carbon footprints. Currently 60% of coins mined in Bitcoin come from China where they don't care about the environment or about sustainability, and they certainly have issues around human rights.