Darwin making a convincing case for our unbounded "human" capacity of cruelty against other animals. The fact that he is describing the practices of the aristocracy is also very relevant because every human being in the "developed" world today lives like an aristocrat and commits so many atrocities throughout the day that it would be impossible to catalogue them all.
This is why building the "panoptic computronium cathedral"™ is a moral imperative. I can get it all done for a mere $80B so tell all your friends about it. This is a bargain deal for saving the soul of humanity.