Well if you consider the 14th amendment as part of the "whole cloth" of the Constitution the I agree. But why was the 14th needed? Article IV did not establish the rules of citizenship or naturalization other than requiring that they be entitled to all of the privileges of said citizenship.
Half of the 14th amendment is jus soli, born in the US. Half of the 14th is everything else, including jus sanguinas if Congress makes a naturalization rule along those lines. And of course, it is expected the people will want a rule that makes their blood line into citizens.
The 14th amendment was needed because some states refused to grant citizenship to children born of slaves, making Art IV useless. Congress can't compel a state (which is a nation unto itself) to change it's citizenship laws, but it can make US citizens out of persons the states were obstinate about.
I have a sense that you are quite open minded about this, and I thank you for that.
Nor did it establish all the rules that would be given full faith and credit (Art IV, Sec. 1). To figure out who is a citizen of the US under Article IV, one has to look to state law.
Federalism.