I'm not fixated on either one. I'm just not dismissing the events that came before the shooting began. Even the video itself has more context than "man kills man and woman". Better question is why focus solely on the murderer when there is clearly a bigger picture here?
If you'd like we can just agree that the guy appears to have been a stone cold psychopath to have gunned down people in such a brutal and methodical manner. If you don't care about any events leading up to the murder, that's fine. I'm not going to make you care. However, I think it's important to recognize those events and possibly explore what could have changed the outcome without ignoring ANY of the wrongs that led up to the incident.