Some of the books are clear on that. Those books are also clear that things like "using tranquilizers" are Evil acts. Those books are canon, but caring about them makes the game stupid. Other books portray necromancy as simply dangerous, in the same way that nuclear power or industrial machinery is dangerous in the real world.
It solves the problem of "your enemies get to take combat actions". If your party can't kill enemies who cannot attack them without spending further scarce resources, that's a bigger issue.Stinking cloud in the example doesn't actually solve the problem, though. It makes the problem easier to solve.