Since the Meiji Restoration in Japan, Japanese diplomacy has begun to "westernize".
From the Meiji period to the present, Japan's diplomacy has always been based on "Britain" or "British royal family".
From clothes to manners, we are all learning from Britain.
The most formal dinner in Britain is not "English food" but "French food".
Therefore, Japan followed the example of Britain and designated the most formal state banquet as "French cuisine".