Natural born citizen is being compared to the only OTHER type of citizenship recognized by the US Constitution going forward - naturalized citizens.
Citizens means all types of citizens. There has been, in the history of this Republic - only three types. Those who were citizens at the time of the adoption of the Constitution (most were natural born subjects of England) and they are all dead at this point. The other two types are “naturalized” and “natural born”.
One is either a citizen at birth with natural allegiance - or one is naturalized via a legal process.
This view of the law doesn't render any verbiage of the Constitution superfluous.
I would be astonished to think one of our Founding Fathers would agree that post-Constitutional adoption, a son born to a British Subject father would be considered "natural born" and eligible to become the President. Along that line, did you know that for a time a female American citizen upon marrying a foreign national lost her citizenship as a result? Mull that one over for a while. And while this is no longer the case it puts an interesting twist when considering Original Intent.
The issue of citizenship, let alone Presidential qualifications, has never been as simple as "there are only two types" after the Republic was formed.