And what court case backs up your claim?
Wong Kim Ark, 169 U. S. 649 (1898)
Montana v. Kennedy, 366 U.S. 308 (1961)
Rogers v. Bellei, 401 U.S. 815 (1971)
Fiallo v. Bell, 430 U.S. 787 (1977)
Miller v. Albright, 523 U.S. 420 (1998)
Tuan Anh Nguyen v. INS, 533 U.S. 53 (2001)
Other than Wong Kim Ark (cited because it shows how the "two types of citizenship" argument is derived, and how it operates), the fact that those cases even exist, depends on the subject having naturalized citizenship (or arguing that they are entitled to naturalized citizenship).
None of those cases would exist if the subject was NBC. A different set of cases illuminates how one can lose US citizenship, and a first premise is that US "natural" citizenship can only be lost by voluntary action. The persons in the cases above did not volunteer to "lose" citizenship (Bellei lost his).
There are hundreds of cases in the Immigration Court books.