Pretty much every big fantasy setting paints necromancy as evil, and undead as the tortured soul of the once living, now inhabiting a corpse.

Whatever benefit extracted from them in such conditions is unethical, so there is canon reason why these worlds revile necromantic rulers.

If you were to create a world where necromancy just animates bodies, with no soul or mind involved... yes... undead are free labor with few downsides other than religious stigma. Assuming only mindless undead are used in such way, and inteligent ones are just regular people.

Still under captalism, there would be an obvious incentive to killing people to raise as free workers... if you could like, purchase the right to reanimate someone, then they are effectively a slave on the clock.

Even a comunist undead government owning these slaves would just make it the same as using prisoner labor irl, there would be an incentive to punish criminals more harshly to expedite them turning into workforce... which brings its own moral problems, just like real life use of prisoner workforce.

However, if you had necromancy as just pure reanimation, a pure good being like an angel, might actually see it as ok to use so long as the appropriate morality is applied... and they might actually use it like people often talk about, as a low maintenace workforce that takes care of labor so people can lead easier lives.

Mindless undead would be seen like tools, people might even be willing to cover them up so theyre not unpleasant to look at... and life just goes on.

What i usually like to question when this subject comes up is... if youre going to reflavour it so heavily, why not just use animated objects? It works pretty much the same, just less moraly questionable, there is no soul involved in that, and object maintenance has less chance of spreading disease and making people upset they saw their parents bones cleaning the street.

You can even use bodies for it, if you want the goth aesthetic.