I personally witnessed a pole transformer blow at night just down my street during a big windstorm. It definitely boomed with a big blue flash, like these. However it didn't cause the sequential destruction of multiple transformers running down the street. So this vid is odd and interesting.
The NYC freak-out videos are not impressive except as kek. Multiple transformers going out at a power station would cause many blue flashes, because that's what they do when the blow. Muh UFO actually isn't.