Didn't Ainz stop caring about that stuff after he gradually started losing his humanity?
Eh gradual isn't the right word, from book one he's near completely severed from it, not to say his mindset doesn't shift over time but that's more about coming to the conclusion he and the salary man are different people/creatures. Id agree he gets worse but he starts pretty far off the deep end.
Some examples from book one
page 92 At the same time, he felt a strange sense of completion and satisfaction, that this was his real body, despite it being completely different from his old one. Perhaps it was because of this feeling that he was not afraid, despite his transfiguration into a set of white bones
page 144 Momonga scoffed, intending to change the image. This village had no value to him. If he could extract more information from it, perhaps he might have a reason to save them. But as things stood, there was no reason to save this village. He should abandon them. Momonga was taken aback by how he could make such a heartless decision. A cruel slaughter was occurring before his eyes, but the only thing he could think of was the good of Nazarick.
There was nothing like pity, anger, or worry, basic human emotions anyone should have. It felt like he was watching a TV show about animals and insects, where the strong ate the weak. Could it be that as one of the undead, he no longer considered himself part of humanity? No, how could that be? Momonga struggled to find an excuse to justify his thinking
page 240 Ainz had once been a human being, and now he was undead. From just now, he had sensed that Albedo hated humans very much. However, it did not upset him or make him feel depressed. Rather, he felt that such thoughts were quite suitable for the inhuman Guardian Overseer of the Great Underground Tomb of Nazarick.
The racial changes brought on by coming to new world are far more insidious and in depth then the anime ever really lets on. Suzuki was a human man, one who remembered a human life but on entering his body there is no sense of wrongness, instead it feels as if he's always been undead despite knowing that's not true. Thats a deep level of mental fuckage right there, to fundamentally not feel wrong in a body totally divorced from your old one, to not be bothered by your emotional connections no longer working the way they used to.