World was not aware of crypto currency until 2017. No one consider it seriously and that is why many criminals took advantage of that because it is decentralise and no one is controlling it. But like many countries are working on it this issue will get resolve in couple of years .
It was used before 2017 really actively. Moreover, it is curious that Bitcoin is not the most popular cryptocurrency among hackers and those, who are connected with the criminal world. The number one crypto in their "society" is Monero. Thanks to the true anonymity of this altcoin, it is a real tool in the hands of criminals. Besides, they like Ethereum and Bitcoin Cash very much.
Now that everything literally requires KYC criminals will have a hard time I guess, also I think this is the reason why Korean exchange delist any privacy coin simply to prevent any criminal activities and it seems so many exchanges out there also trying to delist. if that's really necessary to be done then so be it.