As I explained, it doesn’t, which is exactly what my point is. If changing a race of a fictional character doesn’t add to the story, then why would you change it?

It was already changed once to make it white by Disney. Anderson, the original author, certainly didn't do that. If you're opposed to changing it your beef is with Disney for making Arial white when it wasn't stated she was from even from the beginning.

As in there is more value to keeping true to the original character, regardless of their race.

No there isn't. Many of the historical characters in fiction in our western culture can be traced back to our racist past. Keeping that pattern merely reinforces that exclusion. This is especially true where it adds no value to keep it exclusively white. An even more extreme version of this is historical white actors playing minority characters playing up obvious racial stereotypes. A great example of this is Mickey Rooney playing the Japanese character of Yunioshi in the 1961 movie Breakfast at Tiffany's. If there was a reboot made of this movie today, would you argue that another white actor should play the Yunioshi simply because Rooney, a white man, played the character in the original telling? The author of the novella, Truman Capote, certainly didn't say the Yunioshi character was a white man pretending to be a racial trope of a Japanese man.

Changing it sends the message that there is something better/worse about certain races (in general or in the specific story). I don’t support that (unless it adds to the story).

Thats a really strange take to me. I could use nearly the exact words in my argument to support having other race actors play the parts. You're arguing the fake creature a mermaid's human half should stay white because it would be worse to have a black actor playing that part.

Maybe that’s not the message you get when you see race swaps, but I usually question motives behind decisions.

Not even a little bit. Did it upset you when the Broadway actor Leslie Odom Jr. played the part of Aaron Burr in the Broadway musical Hamilton? The historical figure of Burr was a real person and objectively white, but Odom Jr, a black man, played him on stage. Did you find that inappropriate or importantly un-authentic?

I mean I would sort of agree that most of the time it doesn't really add to the story that much, or, isn't that valuable, because mostly, from what I've seen, people would much rather have their own stories with their own heroes and role models that are natively written to be their same race. I.e. people like miles morales, people care much less about the little mermaid. It's less valuable, you're kind of, partially right to decry it as being surface level, pandering stuff.

At the same time, I would say that the upside people see generally about these stories is really just that they can see and associate themselves with the role models. This is especially important for kids, who are going to be more prone to relating with things on a surface level, I think, but I think it's probably important, in general, to be able to see role models of a variety of skin tones, cultures, whatever, in your media. If I'm remembering, there are actually studies on this sort of thing, that increased diversity in media consumption can decrease racism, though, I'm not sure to what extent that's correlational. I think it was pretty directly causal in the studies I'd seen, but I could be misremembering, I don't really know shit, I'm just a dude.

I think my main disagreement with your point is that I don't really think it's taking away anything from the story to do a race swap. It's pretty much strictly neutral, to possibly good. I think this is outweighed by the quality and disadvantages of doing a stupid live-action adaptation of a previously existing work in general, though, at least as far as artistic merit goes. I straight up don't think I understand the position that, say, changing the little mermaid to be black, implies that black people are, say, better than ginger people, or something to that extent? That ginger people are nonexistent? Hear ye on this theory: Perhaps it is the case that, when adaptations of common works are remade, side characters tend to be ginger specifically because they are side characters. Gingers with obviously freckled faces tend to get slotted into side-roles because they don't conform to the classical standards of "whiteness" as much. Obviously, if I were to do a very cheap, stupid re-adaptation of that work, I'd race-swap the side characters, over the main character. This isn't really true of the little mermaid, but you can see that this logic holds for a lot of other works that people tend to complain about, when they complain about race-swapping. It's possible that it's not so much a specific decision, as a kind of, cynical marketing decision. I mean, you can even see this straight up just in the idea of re-adapting existing works, rather than creating new works that just involve black writers, or what have you.