In 3e it was the evil descriptor, not the fact that it was necromancy that was relevant RAW.
RAW Deathwatch had the [Evil] descriptor.
In 3e RAW descriptors govern how a spell interacts with alignment.
"Most of these descriptors have no game effect by themselves, but they govern how the spell interacts with other spells, with special abilities, with unusual creatures, with alignment, and so on."
Saying that descriptor alignment spells interacted with your alignment seemed RAW, how it does so seems left ambiguous.
Saying casting an [Evil] descriptor spell counts as an evil action seems consistent with RAW separate from any moral consideration of the action. So multiclassed paladins in 3e should be cognizant of that before casting [Evil] descriptor spells such as Protection from Good.
Other necromancy spells do not have the [evil] descriptor, Inflict Light Wounds for example from the cleric list or Finger of Death from Wizard and Druid lists.
In 3e generally spells that create undead, spells that specifically interacted with good or evil alignment, and a few select others have the [Evil] descriptor.
Thanks for that, I did try to look it up but the page I found wasn't clear. I haven't played 3.5 in over 10 years. I don't remember anyone ever using it so it doesn't ring a bell. I would agree it's an odd spell to attach the evil tag to, but what the evil tag means still seems to be a "ruling" not a rule