If the feature you misused wasn't a part of your driver's ed class/driver's license test, and was dangerous enough to cause a crash if used improperly, perhaps Mercedes is at fault (to whatever degree) because they didn't do enough to ensure that drivers knew how to use it. Yes, technically, the driver may be at fault because, well... they're the driver, but this isn't something that is "either/or" - both can be at fault.
Drivers need to be paying attention, but is it not possible that Tesla could also do more to make things clear?
The FAA sets guidelines for autopilot, should the NHTSA not do so for ADAS and enforce that on automakers to keep everyone safe? What that looks like I'm no so sure.
I do think that needs to happen. That's pretty central to my point. Holding Tesla liable when the regulators haven't done so, seems like a unfair judgment even if Tesla and so many other automakers can and should do better. But liability should be clearer than a disagreement over the word autopilot in marketing materials.