It was too close and too sudden. The truck should have slowed from further back and it should not have been so close.
I was in the digital map technology business for car navigation systems back in the 90s. There were working nav systems then, but nobody every heard of them. It took years just to get that working well enough that they are all over the place now. Safe self driving vehicles is way harder. Today's truckers are safe from being replaced by this tech I think, but maybe in 20 or 50 years it will be different.
One factor we have all forgotten to take into account....our burgeoning class of parasitic slip-and-fall lawyers.
It probably would not take more than a few accidents before liability issues drove the makers of these vehicles out of the market.
Amen. A human driver would have perceived the slow vehicle and taken corrective action much sooner.