That’s a different point—you can’t conceptualize an orange if you don’t have a word for orange. OP is making the opposite point: you don’t have a word for orange if you don’t have oranges. The absence of a clear word (much less several) for a “nerd” stereotype might reflect a culture that doesn’t create that categorization.
Coming from south Asian culture, for example, we don’t really have a similar concept either.
I get that. I question that you don't have some archetypes, as well.
That is too say, you might not have oranges, but you still have citrus fruit.
And again, coming from southern us culture, we didn't have direct images of the stereotypes, either. That is largely a movie convenience for story telling.
Coming from south Asian culture, for example, we don’t really have a similar concept either.