Digital currency is to change the world, many of which were positive, to a certain extent, they pose a containment of the government, gave the people an alternative, but that doesn't mean they don't need to be regulated.
One of the core reason is: anonymous, do not track, not regulated digital currency will make form a closed loop technology crime, money laundering and terrorist, and disappear from unsolved bits, bytes, while the impact damage with each person in this world.
If every penny of extortion is tracked, is there enough motivation and courage to launch a WannaCry to attack the world?
I aggree that crypto currency should be regulated in most countries since the population is continuously increasing and the market is gradually expanding. Crypto is used in almost anything these days and by anything, it can be used in illegal activities since people know that they are anonymous and they are basically untouchable since no one knows who they are. Although it may not be beneficial to most people, it is what we all needed to ensure everyone is safe and everyone is playing fair.