And Tornado, and Aztec, and all the other similar private exchange mechanisms.
From about 2015 through February 2024, RODRIGUEZ and HILL developed, marketed, and operated a cryptocurrency mixing service known as Samourai, an unlicensed money transmitting business from which they earned millions of dollars in fees.
There's his problem right there, he tried making a business out of this. Paints a big target on someone arrestable and probably means it's not as secure as it could be. The privacy features in stuff like Aztec or Monero are just part of the cryptocurrency's infrastructure, not a separate "service," so there's not much that can be targeted for those.