@Staffan isn’t wrong though. The focus of the setting is Khorvaire, and the major power in Khorvaire was Galifar, a human-run kingdom with subjects of other nations and species, but mostly human. Then there was the Last War, which opposed human-led nations, even if they had mixed societies. Then non-human nations got involved or declared independence, but they were mostly peripherical both in importance and in geography.
Even after the war, when the power of humans is mostly broken, they remain majoritarian in population and influence in the highest number of nations and dragonmark houses.
What Eberron does have is a high number of peripherical nations that have few humans and little human influence/power/leadership, moreso than any other official settings. So while Eberron is less humano-centric than other settings, humans are still dominant in the regions Eberron focuses on, both in population and in power.