It was always really inconsistent. Some authors treated Alignment as "just kinda your vibe", some as "a combination of cultural factors and divine meddling", and some as "intrinsic cosmic morals", some both but for different things (humans vs Outsiders, etc). Negative Energy and undead as being an Eeeeevil Spookyforce or Basically Just Radiation.
That kind of unaddressed inconsistency fuelled, and still fuels, endless repeats of the "Is Necromancy evil? What if my skeletons are used as agricultural robots to allow for a higher standard of living?", where everyone talks past each other based on what part of the texts they read and settings they play in.
Garth Marenghi never said a goddamn thing wrong in his entire life.