Given that the most universally agreed to counter examples are diplomats and invading armies, I'd say a reasonable non-lawyer interpretation is that "subject to the jurisdiction" excludes people who are in some way under the authority or control of a foreign government even while in the US. They may be physically here, but they're presence is on behalf of a foreign government that has jurisdiction over them even while in the US. US law might apply to them in varying ways depending on their status, but there is still a distinction that does not exist for other visitors. Maybe less about the question of whether US law applies at all and more about if US law applies equally beyond the 14th amendment and if any other government can lay claim to authority.

You could potentially apply this to temporary tourists as well, but the linkage between them and the government of the country they are coming from is much weaker since their presence typically doesn't have them acting on behalf of the foreign government or with any special legal distinction.

I'd also pose the same question back to you, what's a reasonable definition of "subject to the jurisdiction" that excludes everyone except US citizens, as many conservatives want, or at least only extends to legal permanent residents?