Saying that a person is a natural born citizen who is born in the US of citizen parents (owing allegiance to no other sovereign) is not remarkable.
What it does not say is that someone is not a natural born citizen who is born in the US with only one parent already a citizen.
Further, this was in the late 1860’s, so not contemporaneous with any Founders. Those Founders in 1790 declared that a child is a natural born citizen even if its parents were overseas at the time, and the father a citizen.
The point of the quote, though, is moot. No one disputes that a child is a natural born citizen born in the US of two citizen parents.
I haven't worked with boolean algebra for quite awhile. But I believe that the relevant wording in both Bingham excerpts that I posted is the equivalent of saying that if one or both parents is not a citizen then the person in question cannot be a nbc, corrections welcome.
It does not say Citizen either it says Citizens, plural.