Once, on a trip, I was introduced to what was proudly considered the most "authentic" Chinese restaurant in town. No slight on the quality of the food, but the menu featured sushi, pad thai, and wonton soup. Many people can't tell the difference between the different ethnic cuisines, unless they're in pretty broad strokes - of course, in America, Chinese food is often not even Chinese. But just as there are American regional cuisines, from gumbo to bagels to cedar planked fish to pemmican, the great major ethnic cuisines from from large countries with regional specializations, but are often lumped together, or not spoken of at all.
At least in the case of Chinese cuisine, mainstream America has started grasping the nuanced differences betwen Sichuan or Cantonese cooking; here in Houston, we are even lucky enough to have a restaurant that specializes in Uyghur cooking - halal dining. But the other night, I spoke to someone who said, "I don't like Indian food."
Which is a pretty broad statement. India is a huge subcontinent, with many major regional cuisines. Indian cooking is as varied as the heavily vegetarian Gujarati cooking (I don't often see dhokla served in Houston, despite our huge IndoPak population), to the more sophisticated Bengali set meals. And then there's Goa. Goan cooking was heavily influenced by the Portuegese, and thus, surprisingly includes pork as an ingredient. You'd think this should settle well among Texan palates.
Despite our proximity to Mexico, we don't really celebrate the diversity of Mexican cooking styles - we are so heavily ensconced in Tex-Mex that the more localized flavors of Oaxaca, Sinaloa, or Baja have a hard time finding a foothold in the perception of Mexican cooking. Same can be said for Filipino or Thai or Malaysian cooking, where the regional specialties of Cebu, Pampanga, Issan, Chiangmai, or Langkawi seldom surface.