“The right of citizenship never descends in the legal sense, either by the common law or under the common naturalization acts. It is incident to birth in the country, or it is given personally by statute. The child of an alien, if born in the country, is as much a citizen as the natural born child of a citizen, and by operation of the same principle.”
To say that the "child of an alien, if born in the country, is as much a citizen as the natural born child of a citizen" can have no other interpretation than the fact that, although both children are equally citizens, only the child of the citizen is a "natural born" one. Mr Wong was a citizen, but was not the child a of citizen. Therefore, he was not a natural born citizen. Per the majority opinion of Justice Gray, only those born in the US who were "the child of a citizen" are natural born.
First, if your quotation CAN have other interpretations.
Second, your quotation clearly states that Citizenship rules can be changed and altered by Statute.
Third, your citation does not, in any way, say that a person who gains citizenship at birth is not, in any way, a Natural Born Citizen.