Your argument works just as well against any definition of ‘natural born citizen.’ Or even against any requirement for citizenship at all.
It does seem to me that the 14 years residency/35 years of age is a bit of a conundrum.
If citizenship by blood is assumed, that would sort of make sense of only 14 years residency. Born overseas, returns to the US by age 21 and lives 14 years in the USA.
If citizenship by place of birth is assumed, then birth in the USA followed by any combination of months and years out of 35 that total 14 would lead to eligibility for the presidency,
But one has to then realize that eligibility can be revoked for one born to 2 US citizens in the USA if too much of their time is spent overseas. However, the odd circumstance of the person born in the USA and one day later and for the next 21 years in Iran training to be a mullah, followed by 14 years residency has that person eligible for the presidency.
Was that residency rule more likely to have been enacted to bring an overseas birth home, or more likely to get qualifying years under the belt of a person born in the USA of 2 citizen parents?
Just me, but it makes more sense to me that it was intended to bring an overseas blood citizen home.