What about real currency isn't anonymous? If (god forbid) someone took $100 in cash to a pedophile and bought pornography, how is this traceable in the existing system?
And we probably also will disagree that non-traceable monetary systems are difficult or impossible to monitor illegal activities from. Simply the fact that the transactions happen over the web likely makes it easier for law enforcement to get a hold on what types of transactions are happening within something like Silk Road.
Media makes us think Silk Road was not monitored or that it was somehow immune to law enforcement. I disagree whole heartedly.