I don't have an authoritative source, but I've read this anecdote in several of Jancis Robinson's wine columns. Here's one where it is mentioned as an aside: https://www.jancisrobinson.com/articles/chinas-new-connoisse...
All that being said I get the feeling this is something that someone somewhere saw once 15 years ago, and then the story has just been spreading from there.
Do you have a source for this? I would very much like to read it.