I don't think mid-tier only includes Japanese. Since at least the 80s it has become common for Japanese to train as chefs, pastry makers, bakers and cheese makers in Europe and NYC. They usually return and open up their own small restaurants in Japan. Tokyo is full of micro restaurants with 12-30 seats that have been started this way and their quality is very often top notch, so much that it is now often cheaper and better to eat certain dishes in Japab rather their original place. For certain things Tokyo has developed enough that Japanese can now learn it there just as well - Napoli Pizza or French pastry are examples. This goes all the way back to Tempura, a Portuguese import.

What is missing is the more exotic stuff. Latin American, Middle Eastern and African cuisines are underrepresented compared to Western megacities.