Abusus non tollit usum.
There is a legal aphorism "Abusus non tollit usum" - which is abuse does not take away from legitimate use. Yes, cryptocurrencies can be used to do bad things, but so can Microsoft products.
Radiation can be used to kill, but it is also therapeutic.
What has to be established is the harms caused by cryptocurrencies far outweigh the good, and the good can be obtained in another way. The object raised is that the cold monster of the state wants to be able to see everything that is done.