In the Olympiads, I can only think of Keres. (Botvinnik was born before 1917, but I suppose that’s a quibble.) In the national championship, certainly. Flohr. Mikenas. Petrov. Lilienthal is borderline; he was born in Moscow of Hungarian parents, who returned with him to Hungary shortly after his birth.
Has anyone pointed out that a “native-born” rule would have excluded Reshevsky?