This doesn't address soft failures, though. What if the worker didn't fully tighten them to spec but did partially tighten them? What if the bolt was cross-threaded, how could you tell from a video? The amount of camera angles and quality of cameras needed to actually make these calls seems like it would be nigh-impossible.

The data-to-noise ratio of video is pretty bad (most of it going to be wasted on data for... the factory floor or whatever), compared to something like logging the torque of every bolt on the line (which, they already do in some situations).