Although I agree that the comment to which you're replying deserves a bit of dismissiveness, I can't help but think that your response is overly colored by the

Although I agree that the comment to which you're replying deserves a bit of dismissiveness, I can't help but think that your response is overly colored by the "speed kills" rhetoric we often hear. I'm pretty sure, though, that the autonomous vehicle collisions that have made the news lately haven't been at "highway" speed and that that's true of most fatalities (possibly because most vehicle miles traveled are in dense cities?). Now, that isn't to say that we've ever had 45mph or even 25mph heavy objects constantly moving around us in our evolutonary past, either, but the occasional fast predator wasn't unheard-of and a particularly fast one survives today. Moreover, the typical difference in speed between (unpredictable) objects in traffic is much closer to human walking or running speeds. We get into trouble when there's simply too many of them or the difference in speed gets too high.