It’s possible the victim being black played into some prejudice the shooter held that helped him more easily associate a minority with being involved in crime. Studies show older people possess more prejudice. Their brains shrink and with that so does their inhibitions to not act on it.
The article refers to a black kid getting shot down by an elderly white guy for ringing the wrong door bell a few months ago. It’s a topic worth exploring.
This particular shooter sounds like a crazy and hateful person. The scam is terrible but by no means justifies him executing a woman.