This idea is obsolete and is what government agencies hold onto as the reason for enhanced cryptocurrency regulation. Cryptocurrencies do not have dual sides, they (Bitcoin specifically) are assets with value and as such it can be used in situations of wealth transfer just as all other assets and fiat currencies are used. Bitcoin does not facilitate scams and the agenda of crime fighting does not have to target digital assets.

Any agency claiming to fight crimes in Bitcoin is just looking for a way to regulate and control the market and transaction flow within it as far more scams are run on other medium of exchanges, But most of those other mediums are already regulated, Bitcoin however stands out as a decentralized network - hence the cryptocurrency scam agenda.