unless American soil is some form of magic pixie dust, it has zero impact on citizenship status.
being born to an American mother gave him US citizenship at birth, regardless where he was born.
only quest would be whether he chose American or italian, via his father
The language of the 14th amendment is clear.
People born in the US or its territories are considered a US citizen at birth, regardless of their parents citizenship status.
Without an amendment or Supreme Court decision clarifying the 14th that is the law of the land.
In order to change it, steps must be taken that involve more than histrionics on an internet message board.
8 FAM 300 U.S. Citizenship and Nationality
(1) Jus soli (the law of the soil) - a rule of common law under which the place of a person’s birth determines citizenship. In addition to common law, this principle is embodied in the 14th Amendment to the U.S. Constitution and the various U.S. citizenship and nationality statutes; and
(2) Jus sanguinis (the law of the bloodline) - a concept of Roman or civil law under which a person’s citizenship is determined by the citizenship of one or both parents. This rule, frequently called “citizenship by descent” or “derivative citizenship”, is not embodied in the U.S. Constitution, but such citizenship is granted through statute. As U.S. laws have changed, the requirements for conferring and retaining derivative citizenship have also changed.
Through a congressional statute. This did not make him a "natural born citizen".
Aldo Mario Bellei lost his US citizenship for failing to comply with the requirements congress set out in the naturalization law they created to grant such children as him, citizenship.
Natural born citizens don't have to meet any requirements for citizenship, and their citizenship cannot be taken away from them for failing to do something.