Idk maybe since it was a high way they couldn’t slow down in time especially cause it was a big truck?
It also looked narrow? So maybe it was a one lane on an underpass branching into another highway/street. Idk something like that
I don’t know how it is in Japan but in Germany it’s important to, before even wasting one second on checking on the passenger(s), put up warning signs up to 100 meters before the accident, or at least turn on the hazard lights or emergency flashers or whatever you call it, to avoid exactly these issues of cars and trucks being unable to stop in time. And while I can’t see whether she turned on the lights, it did not seem like she took the time to properly secure the area, before aiding the injured.
But I can also confirm that when observing truck drivers you will see them do the most unimaginable things. Reading, texting, shaving, sleeping...
Watching TV...
How come the truck driver didn't break earlier?? There's no way they didn't see the smoke & the crashed car. Plus, it's a straight road. Are they drunk, on the phone or sleeping while driving??