I read a recent publication that says, According to CipherTrace: Thefts, scams and other misappropriation of funds from crypto holders and exchanges have resulted in a $4.3 billion in losses in the year 2019 so far, and this will likely go on until there is sufficient oversight for cryptocurrencies and blockchain related activities because the world givernments cannot relinquish control to the masses in the way that the blockchain wants.
Regulations is needed to attain mass adoption
Truly there are various illegal activities in the crypto space because of its decentralized nature. This is one of the reasons why probably many countries government are not ready to legalise it. But nowadays, several efforts are in place to mitigate these activities and that is why crypto is gaining more trust among individuals and governments.