I don't care whether a meal passes some authenticity test, but I very much care that the meal should pass an "Is it good?" test.

Removing for the moment the ambience and service of an eatery, the essential elemants of the food served are the quality of ingredients and the skill of the chef and staff. In my experience, the quality (and very especially the freshness) of ingredients is almost always very high in Hong Kong and what little of China that I've seen. I don't know of any Asian restaurant that I've been to in the US where the ingredients are as fresh as in HK/China -- for example, where the prawns are brought to the table while still alive and swimming, then tossed into a boiling broth.