[andrewflnr]

  Astronomers know that as recently as a few hundred years
  ago, the Milky Way’s central supermassive black hole was
  producing much more radiation.

Wow, what a near miss. Would that have been visible at all? To think that if human technology had kicked off a couple centuries earlier we might have observed a black hole eating something already, that the answers to our questions about black holes could be common knowledge... wow.