I was talking more about how Italian Americans that are native speakers tend to speak a dialect that largely derives from Sicilian and other southern dialects that have since fallen out of use in favor of common italian, which is technically an entirely different language based on a northern dialect.

The joke is that these sicilian speaking mafiosos will sound like the american cousins because the dialect the Americans speak is closer to sicilian than the modern italian Sicilians are more likely to use in their everyday right now.

It’s actually a pretty hilariously documented phenomenon across the old world and in multiple places within the new world, where countries that endured a nationalist unification period adopted a common tongue, and in doing so diverged the language from native speakers that had migrated to the Americas.

Similar sitch with “inauthentic” ethnic cuisine being criticized by others in America and elsewhere in the Americas, it’s not different because it’s inauthentic, it’s different because it’s a preserved cultural artefact which predates a prescriptionist change dictated from the elites (who tended to be from a single language/culture group) to the common public, while the forms seem in the Americas are those predating cultures and traditions.