One of the founders of Tornado Cash, among the most popular services to hide crypto transactions, said it doesn’t need to comply with sanctions https://trib.al/yOHhCJY
Tornado Cash uses @chainalysis oracle contract to block OFAC sanctioned addresses from accessing the dapp.
Maintaining financial privacy is essential to preserving our freedom, however, it should not come at the cost of non-compliance.
https://etherscan.io/address/0x40c57923924b5c5c5455c48d93317139addac8fb…
RPC call was just faster to implement. Chainalysis has sanction screening API, but I've sent my application for access and didn't get any response yet.