Sure we're talking about very few deaths, but it still is a design flaw, as it has trouble recognizing a specific kind of motorcycle. I would say that makes it more of a bug that hasn't been patched out rather than a mere statistical error, but I am not well versed in actual software development so someone else might come up with a better analysis.

As for human input, I agree, this is a very different case from, let's say, an experimental self-driving car. However I still believe Tesla's decisions play a part, for example the naming scheme they chose, autopilot rather than assisted driving or some other admittedly less enticing name.

Of course one might say that people with a car license should be able to see through basic marketing, but it might nonetheless influence people's behaviour, even if just subconsciously.