I know of no amendments to Article II. Either we have a Constitution that means something or we throw in the trash can. As I understand it, the NBC requirement means born in the U.S. to two U.S. citizens. There is nothing irrational about the framers wanting to be extra careful when it came to the qualifications of the individual holding the highest office in the land. They wanted someone whose loyalty to Country would be beyond reproach, who was born to to U.S. citinzens and had spent a lifetime in this Country being nurtured in what it means to be a true American. If being born to two U.S. citizens was enough, could a guy who was born overseas to U.S. citizens and lived in the foreign country all his live qualify as an NBC citzen? Think about it?
Not to belabor the concept of an “evolving constitution”, but in the time of the founders, the concept of casual travel to foreign countries was unknown. You didn’t “vacation in Europe”, so they didn’t really have to think about whether US parents might be off on a Russian cruise vacation and go into labor and have a kid in St Petersburg.
And they would NEVER have thought about a soldier and his wife being deployed long-term on foreign soil, and having a U.S. Citizen child on a military base in Germany.
Interestingly, because Embassies are considered “U.S. Soil”, a child born of U.S. citizens in an Embassy would be NBC, but if you drove them to the local hospital to have the kid, technically the kid isn’t NBC. Certainly THAT was not something the founders really considered.
The bigger issue is that the term “natural born Citizen”, at the time the constitution was written, was not a term of art.