Unfortunately, the world we've built allows people like him, more or less, to get away with it. In the old world, being completely intolerable to your social web meant that at best, you'd be made a pariah by people you need to rely on, at worst, it'd get you punched in the face. Being able to live online means that you can find just enough impressionable people to reward you for being a shitbag, and none of the mechanisms of shame and ostracism that used to bully people into not being shitheads anymore still seem to apply.