The problem is that magic isn't replicating 19th and early 20th century technology in the Eberron setting. It's creating armies of mechanical men, rivety giant robots, and flying ships that look and feel like seagoing vessels. Combine that with the specific 19th century technologies that magic replicates as part of the setting (telegraphy, locomotives, and continual flame gaslights), and the setting starts to feel like a fantastical 19th century, which is why a lot of people read the setting as steampunk.
If you don't see it, that's fine. We can agree to disagree.
As I said, in some ways, Eberron is more advanced than current society due to its magitech. And while it has armies of mechanical men, giant robots, and flying ships, none of them really follow steampunk aesthetics and its core assumptions. There's nothing particularly clockwork, riveted, steampowered, or Victorian about them. The flying ships, for example, aren't the usual Steampunk dirigibles. There's nothing particularly mechanical about them. The entire steampunk genre likes to give the false perception that their creations are the result of scientific engineering. It attempts to deceive people into the fantasy of thinking that this is scientifically possible, and people basically nod and go along with it. But in Eberron, the images are oozing with magic, such as bound-elemental rings surrounding the flying ships. The moment that you basically say that "magic did it," then it seems to me as if you are breaking a fundamental aesthetic of Steampunk. And the warforged don't look like conventional Steampunk clockwork automatons, but golems of metal and wood. And another glaring absence of the steampunk genre: where are the guns in Eberron? The images are filled with bows, swords, axes, and the like that largely break any sense of steampunk immersion. The closest that we get are with wand duelists, but this evokes Harry Potter more than anything nowadays.
Those elements aren't necessarily associated with noir. I mean, putting aside "archaeological-focused universities" and "competing trade families," which aren't associated with noir at all, the elements you've listed are just elements of spy fiction and crime fiction. James Bond films contain many of those elements, but nobody would confuse them with noir. Meanwhile, Sunset Boulevard contains none of those elements, but nobody would mistake it for anything else.
They aren't necessarily exclusive to noir, but intrigue is closely part of noir. There is very much a Maltese Falcon vibe to Eberron. You could basically run an adventure set to the movie, but with a dragonshard as the MacGuffin. Or you could draw from noir-inspired sci-fi, such as Blade Runner, Minority Report, or Alphaville.
Noir is notoriously difficult to define, and I am not going to attempt that here, but it's less about subject matter, and more a matter of tone, themes, and (of course) visual style. While it's possible that other materials hit closer to the mark, the Eberron materials I've seen don't even seem to make an attempt at noir.
So you mean it's about like how Eberron isn't Steampunk? There are a number of Eberron adventures that entail murder mysteries. It's not necessarily "true noir," but it's clearly attempting to evoke a similar feel.
in a QnA on
https://www.twitch.tv/explodingdice Mike made a few more remarks about campaign settings.
Basicly he siad that if they where to do a campaign setting it should be diferent enough to draw in people currently not playing DnD, and not just another option for existing players.
I'll admit that I'm skeptical that Mearls would know how to do that and which setting that would even be.
