You're right. He didn't make the argument "X should be illegal because Y" but the fact that "X is illegal because Y" raises the question, at least to me, should it be so? Is it rational?
Fair enough. On-topic, I feel the most relevant fact is how many people would get hurt if anesthesia were legal.
http://www.theverge.com/2012/8/8/3177438/cyborg-america-biohackers-grinders-body-hackers