Fanaelialae
Legend
My view on the matter, which I realize diverges from the common wisdom, is that it isn't a problem.I think that right there is the problem. You can create as inhuman a mindset as you can think up, and most players will either ignore that mindset or not play the race at all. So there needs to be a happy medium where the race is alien enough to be different but not so alien that it can't be understood and played.
I'm not saying it's not possible. Just that it's difficult.
Those players who want to engage with the alien mindset will, and it will enhance their experience because that's what they're looking for. Those who don't want, to don't have to, and can play their character like a funny looking human. I simply have the NPCs react to them accordingly. Not in a punitive manner, but simply recognizing that the character is different from the other elves/dwarves/whatevers that they've known. I mean, there are a fairly diverse range of outlooks amongst humans (some of which I find difficult to imagine from my own perspective). I see no reason that other sentient beings couldn't have similar neuro-diversity.
As an aside, I said this in the other thread so I wasn't initially going to repeat it here. However, I don't see any reason why a campaign shouldn't be inclusive and have diversity. Even if the snow elves in your campaign world have alabaster hair and skin, it's a fantasy world. Whether by some quirk of genetics, act of the gods, portent, or whatever, just work with the player to come up with a reason (which will probably also give you a cool potential story hook that your player is already interested in). In general, I think demihumans should have all the diversity of humans.