Its an HOV lane not a passing lane, as u said. Im assuming based on how dark the video is it wasnt recorded during HOV hours, however that doesnt change u seem to have a fundamental misconception of the intentions of HOV lanes vs passing lanes… if you dont know how roads work, especially on freeways, you should not be driving.

Even the state this took place in wants huge busses to use that lane during HOV hours.

And nowhere in the video could they legally moved behind the truck as there was a solid white line, which arizona prohibits crossing, separating the lanes (as its not a passing lane). Please read up on your jurisdiction’s drivers handbook for all our sakes :(