Not really if the end use case has not been to harm someone by other party, else not just blockchain, but even real money will work as a means in the surge for criminal activities. About drug trafficking, why don't people consider smuggling of gold and other precious metals as well as chemicals in exchange of these drugs instead of blaming blockchain alone every time? I've had been watching this since the beginning and can say that Bitcoins' use is least in such malicious happenings compared to those that are used in real world already like fiat, gold, etc.