"IRS-CI Special Agent in Charge Thomas Fattorusso said: “$2 billion in transactions with an unlicensed money transmitter means $2 billion flowed without any oversight, from whomever to wherever. Because of the company’s disregard for regulation, it’s alleged that Samourai Wallet laundered more than $100 million in criminal proceeds"
Transactions are not unlawful cause you cannot trace the flow of the transaction. The $2 bliiion seems to have just been thrown in there for shock value, giving them a justification to clamp down on the service.
But they were greedy to clamp down Binance which was alleged for money laundering, bank fraud, sanctions violation and others. Binance pairs 4 billion and still existing.