Basically if you agree to the ToS you are telling Tesla - go ahead and experiment on me I won't sue you. If you are not interested in doing that don't use the functionality. I bet the first gentleman who was killed by the trailer very much subscribed to this philosophy because he was genuinely interested and intrigued by the technology and what it could do. He took the chance and paid a price... hopefully he paid it gladly but he knew what he was doing and the risk he was taking because he posted a near miss video on you tube and as per the articles around him he was genuinely proud of his Tesla.
If this guy on the other hand is trying to blame autopilot for his own mistake then he should not get a chance to spoil it for everyone else.