Agreed. John Carpenter purposefully didn't give an explanation as to why Michael felt compelled to kill, at least nothing more in depth than "What was behind that boy's eyes was purely and simply evil." That was all that was needed.
Not only did Rob Zombie take away everything about Michael Myers that made him scary, he heaped on every psychological torture that would turn an average kid into a psycho killer.
Dead parent? Check. (His dad was dead)
Physically/emotionally/psychologically abusive parent/guardian? Check. (His stepfather)
Neglectful guardian? Check. (His sister abandoned her babysitting duties to have sex)
Bullied at school? Check.
Early exposure to sex warping his perspective on things of a sexual nature? Check. (His mother was a stripper, and possibly a prostitute, and his sister has a reputation for being the school harlot)
Torture, kill, and mutilate animals? Check.
Hell, I'm surprised RZ didn't make Michael and Judith's dad their mom's brother or first cousin. Or showed scenes of Michael wetting his bed and setting fire to his neighbors' garage. That's about the only thing missing from his redneck piece of trash of a movie.