SCOTUS does not have the last word. The Constitution in its plain wording does, but Congress has to assert that, which it won’t. The Constitution gives Congress sole power to make the rules for citizenship. The 14th, which is so righteously cited doesn’t even address the issue at hand.
The Congress has the sole power to determine the rules for naturalization, not citizenship. In Afroyim v. Rusk (1967), the Supreme Court shot down a federal law that said a person lost his citizenship if he voted in a foreign election. The Court held that the Citizenship Clause, not federal immigration laws, governed the case.
We have to think beyond anchor babies. Does anybody trust the Congress with plenary power to determine citizenship? I don't trust the Congress with the power to take away citizenship. Imagine what Pelosi, Reid, and the Liberal Messiah would have done with such authority.
This issue should be resolved via a Constitutional amendment. I trust the People, an Article V Convention, and the States a whole lot more than I do the Supreme Court or the Congress.