Negligence is already something the courts are well suited to handle. Tesla already has a big incentive to do this well. I don't think they are necessarily negligent here for having marketing material which doesn't 100% cover real world usage. If that was ALL the information customers received I would...but I highly doubt that's the case.
I also take issue with the autopilot name as well, but I do think it's something that can be effectively communicated elsewhere with a product like this - where it really isn't that big of a deal. It is not a large barrier to communicate the immature state of the software and the limited current use-cases to each buyer beforehand regardless of branding.
If Tesla is over-promising and under delivering their relative advances in autonomous driving as a sales tactic, then there is little defense of Tesla if drivers don't read enough fine print to understand the limitations of the autonomous driving systems.
In my assessment, Tesla is not being honest about capabilities. If they were, they'd have used the naming strategy that comes up with "adaptive cruise control," not "autopilot." (Sidebar: I don't care what "autopilot" actually means, the general public thinks it means computer magic makes a plane all by itself.)
Having misleading branding and marketing materials that show the CEO operating the product in an unsafe manner convey a message to viewer on how seriously to take the warning. They're giving the impression that the disclaimer is "under-cooked meats can carry food borne illness" on restaurant menus. The "don't try this at home" cover-your-ass warning while winking to try it at home.