CipherTrace just published their Q2 Cryptocurrency AML Report and found it interesting that Bitcoin still reigns king in dark markets and cybercrime. Most people associate privacy coins even just 4% involve Monero.
Even in the case of malware and ransomware, ETH used in only 1% of instances and BTC used in 98% of cases.
https://ciphertrace.com/q2-2019-cryptocurrency-anti-money-laundering-report/I do not think that these statistics are real. In the USA and the European Union, studies have already been conducted on this subject and it has been established that up to ten percent of bitcoin was used for illegal purposes. The reason for this is only the relative anonymity of bitcoin. But coins with a high degree of anonymity - Monero, Zcash, Dash were used much more often. Therefore, the Japanese government has long banned the use of these coins.