On the other hand, "anonymous" is to some degree like computer "security". Secure against what threat? Anonymous to who?
Paper money is certainly traceable to some degree. Plus it almost requires you to meet in person, where the other person in the transaction can see your physical appearance (or your proxy/accomplice's).
Both mediums of exchange have similar risk profiles, but they are a little bit different. Not sure that I'd argue one is better than the other, generally. Depends on the use case.
Plus there isn't any way to order 500 hits of acid from 3 timezones away in-person without a lot of issues. Lotta ID checks at the airport, and lots of cameras on highways.
If something goes weird with the darknet shipment I walk, feign ignorance, burn the laptop. If I'm carrying drugs on a plane and get busted then it's on me, no question.
But yeah, if you didn't pull good OpSec in 2014 it's possible the feds might link it to you in 2023, or whenever they get around to it.
I never understood why people described Bitcoin as an anonymous currency, it really isn’t. Arguably physical currency is much, much more anonymous than Bitcoin.