"French culture is whatever happens in France" This sounds to me as a bit tautological. If we move 200 millions from china in 1 month, you wouldn't say "french

"French culture is whatever happens in France" This sounds to me as a bit tautological. If we move 200 millions from china in 1 month, you wouldn't say "french culture is about eating rice, and french people generally look like chinese". Culture sometimes change intrinsically, but sometimes because of huge foreign influence or demographics ( invasion being historically the most influencial one). Doesn't mean you can't observe the change when it happens and judge it.