Terrible story, but probably an example of inattentional blindness. The person driving the car wasn’t expecting to see a large tractor-trailer blocking the road (and the trailer part is often the same color as a grey sky), so just did not see it.
I have seen things like this happen personally (though not resulting in death) so I know it occurs. I’m always surprised by what people do not see/notice as I have a really wide attention and see things others miss most of the time.