I’ve seen this before. It might cross a state border, but it is certainly not a main line. I forget where it is. As I recall, this is a ‘short line’ railroad that was abandoned by major line, to be picked up by a ‘short line’ operation to serve the remaining few customers. The short line cannot afford major track renovations, so they just operate slowly (walking speed) to minimize damage if they do come off the rails. The lumpiness of the track is accentuated by the use of a long telephoto lens to make it look much worse than reality. But the loco DOES wiggle because parts of the track are no longer level.
There is absolutely NO comparison to the Norfolk Southern mainline where the toxic derailment happened. That was not caused by trackage. It was a hot axle.