Originally Posted by
ForsakenRoe
The whole point of several Jobs, and their associated questline, is 'hey this Job is really bad and dangerous, but you're showing how it can be used for good'. Like BLM is the Job responsible for half of a Calamity. WHM is the Job responsible for the other half. RPR literally summons voidsent which is like... one of the biggest 'don't do that' moves in FFXIV lore. DRK is viewed by the Ishgardians as 'heretics', but DRKs bring justice to those who the regular 'laws' can't apply to. WAR can very easily become an uncontrollable weapon that destroys the surrounding area in its misguided rage. I don't know where the limits of SMN's summons are in terms of power level, but IIRC the practice (in Allagan times) was very taboo because of the danger it posed (Tempering), etc.
A Necromancer could just as easily be done by FFXIV, with lore being written via Job quests as like... 'Most Necromancers use Death-Magic to try and extend their lives, attain immortality, etc. You, applying the 'true' purpose of Necromancy, bring peace to the souls of the departed who still had some lingering regrets they could not leave unresolved'. So now you have the current Necro's we've seen (the POTD guy, etc) as 'misusing the power of Life and Death', and you are a... slightly less immoral Necromancer. Just as 'morally grey-zone' as BLM currently falls into. It would give opportunities for very varied (moral-alignment-wise) quests. On the one hand, a very positive aligned quest 'bridge the gap for two people who were in love in life, so they can tell each other how much they love one another one last time'. On the other hand, a much more morally-dubious quest of 'helping the spirit of a victim of a horrible crime, by tracking down and exacting revenge upon the perpetrator (presumably by killing them)'
I think the main reason, is less about the appearance of it being 'evil', and more about the cultural sensitivity towards the concept of 'death' in Japan. They use 'Yon' instead of 'Shi' for the number 4, Hotels might skip over the 4th Floor (usually naming it 3A or just skipping straight to 5), etc. TBH I'm kinda surprised Necro's getting put in Occult Crescent