My head canon is that the shows simply show the aliens from a human perspective. A Klingon would laugh if you told them Klingons are a monoculture. In fact, they would probably pull out a knife and threaten to slit your throat:

DO ALL KLINGONS LOOK ALIKE TO YOU??

That’s because all sci-fi alien species are monocultures

And all sci-fi planets have exactly one type of terrain/biome.

You got desert planets, swamp planets, forest planets, ice planets, hell -- even city planets ... but you never see any planet that has similar diversity to Earth ... or even similar diversity to California. In sci-fi, every planet looks the same across its entire surface.

They also usually have one place of origin, or if there are multiple, it's just vaguely in a direction (lots of planets have a north), or an off-world colony, so the whole species is named for the planet they came from.

Martians are from Mars, Vulcans are from Vulcan, Humans are from Hume, etc. You don't tend to have them mention any more specific regions than that. Where on Earth do Earthlings come from? Why, the Earthling city, of course.

Biomes on planets often too

And if we were writing in German we'd capitalize every single noun, which is simultaneously more and less confusing imo, lol