So, something I dealt with literally just an hour ago seems applicable here.
I do a live-writing thing that is... sort of half play by post, half novel, half something else. During the latest run they picked a big ability to use for a dramatic finish, butas a price something bad had to happen, and when I put it up for a vote one of the options was the techno-virus they were fighting off from an NPCs mind got rooted in deep and was going to become a more permanent part of that character, though the NPC was going to retain full control of their faculties.
Some people in my chat took exception. One person even called it a betrayal.
See, I, as the author had seen this entire quest line as freeing the NPC from the potential control of this techno-virus. Therefore, with her in control, they had succeeded.
They had seen it as completely curing her of the virus, and so with part of the virus becoming permanent, they felt I was forcing them to fail at the last second.
My intent and their interpretation did not match up. It was close, but about 20 degrees to the left of where they were at. And while I talked to them, and we talked it through, I think this very clearly highlights that the intent of the author does not mean that the story came across in that manner. Subtle things make a difference.
And, moving this along to races, there are some things that we can do, but that are really hard to pull off. For example of a simple thing, I did a little research and it was proposed that humanoid creatures with horns wouldn't really blush. Instead, their horns would darken from increased blood flow. That is amazing, and super cool.... but how do you describe it quickly at the table? It is still a blush, as in I am indicating they are embarrassed or aroused or whatever else you use blushing for, but it is expressed in a different physical manner.
Do I use the short hand? What if I forget to describe it properly?
I'm also playing a character in a game right now who doesn't have a gender. They are a fae spirit of fire and wind, having a gender doesn't even make much sense to them. I keep slipping up and saying he. Is this because I can't possibly comprehend a person without gender? Well, sort of. I know that there are non-binary people whose gender and ideas about gender are very fluid. I'm not one of them though, so it is very difficult for me to express that, even though it is something that is possible for a human mind to express.
But, even if I understood it better, and presented it... would the other people at the table interpret it the way I intended it?
And at the end of the day, how accurate do I have to be for it to count? I have an idea of a character for Eberron, a human Ancestral Barbarian who is from Cyre, the spirits that haunt him being the souls of the other people from his village who didn't escape the Mourning. I can't portray that character accurately. I can't portray someone who has lost every person they ever known, their home, their land, their nationality, and hope for it to be accurate. Sure, it is a thing that has happened to humans, but words are a poor medium, and they can't convey something that devastating with 100% accuracy.
So, how accurate do I need to be? 70%? 50%? 30%?
And, depending on how low that number is, who is to say that I can't capture 50% of an alien mindset? And who is to say that that isn't enough to make it enjoyable or interesting to try and portray that character?