If crypto does gain massive adoption and you are able to pay for things in crypto, there would be less of a reason for people to cash out into fiat. How would government collect taxes from crypto gains then? Also, if something like ETH becomes big, how is the government gonna stop people from making pyramids, ponzis, and scams in general?
Government can make regulation to collect taxes from bitcoin trading. Every trade we made in market will put taxes by government. I think Ethereum is not a ponzi scheme because its already recognize as digital asset in several country