Title. I want death magic casters. Warlocks are being added to Diablo, three times over, let get Necromancers in WoW. Going to preempt some arguments here.
Too similar to Warlocks: This is something I caught a lot when suggesting this in the far past. Warlocks are not in the same class fantasy as Necromancers. They’re different power sources, different magic classes, different fantasies. They both have pets, so what? Many classes use magic, that doesn’t make them mutually exclusive. Moreover your traditional necromancer (using sources not limited to diablo) don’t really have “Hordes” usually it’s a few handcrafted and invested undead minions.
Too similar to Unholy DK: They don’t use bone magic, they don’t use alchemy, they don’t use curses or spirits, they don’t revive fallen foes, they don’t command golems. Spells that are necromance-adjacent are short lived and not part of wide rotations. Death Knights are Death Knights. If you can understand the delineation between a Demon Hunter, who uses fel magics, demonic magics, and used to be able to summon demons, and a warlock you can understand that DKs are not necromancers.
Those are the two biggest sticking points usually pointed out in the forums. There wouldn’t really need to be any kit borrowing. There are priests and paladins, mages and evokers, shamans and druids. Two classes can share themes and be distinct.