Meh. I like to keep alignment and biology separate.
I get what you are saying. I think you are saying something like, "I prefer to have all biological species be fundamentally similar in temperament and emotional framework to humans so as to avoid demonizing any sentient thing, because here back in the real world where we only have one sentient thing we've seen so much evil come out of people demonizing one another that I don't want to potentially be a part of that." And yes, I can totally understand that and that's a perfectly valid choice and go with it.
But on the other hand, ironically alignment and biology are definitely not things you can keep separate. I mean you probably can ignore biology's impact with anything that more or less shares a common origin and common level of being with humanity. If they are very humanlike in their biology and their creation, you can probably safely assume that they are just humans with a few differences and so their alignment or morality is likely to be similar.
But the more you get away from that, the more difficult that is to sustain. For example, suppose you have some evil Tony Stark who happens to be super misogynist (not that farfetched for Tony) and one day he decides to encode in a machine a copy of himself as a machine, sentient, aware, but hardcoded in the firmware with the fundamental belief that all women must be exterminated. And Evil Tony dies and this race of self-replicating living machines starts killing anything it identifies as female, living out the beliefs of its insane and malevolent creator. They can't be reasoned with. They can't be bargained with. They can only be stopped. You could possibly argue that they are just forces of nature without moral identify of their own, but they've inherited the belief system and moral identity of their creator. In that case, you can't keep biology and alignment separate. And the fact that they are "machines" to me doesn't make a big difference, because well we are ourselves carbon/water machines.
I don't think you can get around that scenario in some form. The one I give is distasteful and far-fetched, but well it's the nature of evil to be distasteful. Demons are distasteful in ways that are worse. It's reasonable to describe the above unwavering misogynist machine as a created silicon demon. It is defined by its behavior but behavior is defined by biology - where in a speculative fiction setting you are often required to have a very broad definition of biology because you have a very broad definition of life.
In a fantasy you will have all sorts of inhuman biologies which won't necessarily have choice and capacity for good or evil as a defining feature.
everything to do with zealotry
Ahh... the good old True Neutral alignment. Nothing is itself evil except that zealotry doth make it so, and the virtue of right conduct is balance and moderation. Very popular view of the world; so popular in fact that it's the reason I stat out human inspired fantasy races as "Usually Neutral".