Money laundering is a major concern and cryptos have made money laundering easier so there is definitely an argument to be mande there. However, just like money, crypto’s have both a bright side and a dark side.
There is a $400 billion industry where foreign workers send money back to their families abroad and majority of these transactions are done via hawala. At the same time illicit trades as we know off s** and dr** industry thrives on hawala networks. transferwise.com is an online remittance service that in a way used hawala as a use case and created a legit repatriation business around it by performing KYC and letting people exchage money by disintermediating banks.
Bitcoin - Open source P2P money says that bitcoin is a payment network and a new kind of money. Its value is based on mutually ageed upon price just like any other currency (exchange rates). If everyone who opens an account at a crypto exchange is KYC’ed well then there is no issue of money laundering while if you use your own hardware wallets and transfer money then there is no KYC involved.
To make long story short, Bitcoin is not bad. If it was bad and used only for illicit trade then central banks would have easily banned it by now. But there are a lot of good sides to blockchain and cryptos which is why it has become so difficult for central banks to outrightly ban them in the first place.