Again, no argument, but travel was probably not generally undertaken for the pure enjoyment of it. Your earlier description of it as a three input AND gate is apt, and I suspect they would have included an OR or two had they envisioned the world today.
I think most don't object to their intent of having the leader of the country be loyal only to us, if that was the reason for the NBC requirement, but today?
We just don't like exclusion, believing instead that everyone is or should considered equal, with equal access to everything, including the presidency, no matter what.
That highest best standard for NBC excludes individuals we know to be loyal Americans and that's not right.
Highest, best standards are exclusionary by nature, and usually for our own good, but we usually take them down sooner or later and often start our ride down the slippery slope that bridges the gap between them and whatever we want, when we want it.
Most of the issues we humans politically fight about are of that quality and I am grateful to the FFs for leaving us with this system where we can argue it out...if we can keep it. Today, we like skiing that slippery slope!