The US dollar exists almost exclusively as a cryptocurrency, and when cash is completely abolished that’s all it will be.
You can speculate in anything, but that doesn’t make the thing you speculate in bad.
Are tulips bad? Do people still make money selling tulips?
It's because cryptocurrencies can be anonymous and so can't be taxed nor controlled . Banks are not even needed. The left hates decentralization. They left want the government to own and control everything (socialism) which is the ultimate centralization.
I'm for competing interests. A privately owned for profit business that has competitors is accountable to customers and the bottom line. A government bureaucrat in a government agency like Comey or Lois Lerner are not to anyone
Sure, tulips are very profitable for the local florist . . .