Online drug markets existed before BTC, and today there is a problem with "mules" being used (people who have legitimate bank accounts that are used to transfer money for groups that engage in illegal activities)

Sending money to a "grey market counterparty" has had workarounds for some time, and continues to have workarounds.

People were fooled into thinking crypto offered anonymity, and were surprised when they realised every single one of their transactions was sitting in the public chain available for anyone to read.

Digital wallets provide LEA's with clear evidence of transactions with a given party when that party's anonymity is unmasked, and it's there in perpetuity.

Had Epstein being using BTC to do business, every single one of his clients would be known.