You make a good point that, blockchain or not, ultimately the problem is not technological in nature. Bitcoin facilitates drugs and hitmen as much as ability to

You make a good point that, blockchain or not, ultimately the problem is not technological in nature. Bitcoin facilitates drugs and hitmen as much as ability to mail someone a letter with bank account details attached (account with money). As usual, the solution is to make the activity not worth the risk by posing as either party.