And where has she shown to have a complete lack of concern or empathy for the effects of her actions on others?

Has she gloated that her follower count has increased? Has she expressed any glee over these firings?

In fact, if you've read the Venture Beat article they assert directly the opposite:

Richards, while standing by her actions, has tweeted that she did not think the developer should lose his job. It’s fairly clear that getting him fired was not her intention.