^Sure, but I'm just saying that in conventional, real-world, the name of a species is uncapitalized. The tendency of science fiction to capitalize species names implicitly equates them with nationalities, which plays into the unfortunate, rather ugly tendency of science fiction to practice racial essentialism and stereotyping. It promotes the confusion of racial identity with cultural or political identity -- like treating Vulcans and Romulans as separate species when they're really separate nationalities of a single species.
It's also just oversimplistic to use the same name for the species, the planet, the language, and the nation. Instead of Vulcans from the Vulcan-speaking Confederacy of Vulcan on the planet Vulcan, why not, say, vulcans from the V'nari-speaking Confederacy of Surak on the planet T'Khasi?
It's confusing to say that Vulcans and Romulans are both Vulcans, but it would be clearer to say that T'Khasians and Romulans are both vulcans.