I agree with you. I think cryptocurrencies offer a new wave of opportunities way beyond investments and the convenience of digital portability.

I'm curious which currencies your friend has identified as never being used for crime ... Cryptocurrencies have no doubt been used for crime and fraud, and they have inherent features perfect for criminal purposes, but I'm pretty sure criminals have used dollars, francs, eurodollars, yuan, and yen for crime too.

The fact is the fundamental enabling technology for cryptocurrencies (blockchain technology) offers tremendous advantages even beyond cryptocurrencies. And cryptcurrencies offer many advantages beyond physical currencies. Undoubtedly, some will evaporate and disappear, but I don't think they are going away in total.

I am curious though ...
What do you think it would take to make cryptocurrencies (or even one specific cryptcurrency) go away?

I have a couple ideas, but I'd like to know what all the readers think.