Article 1 Section 8 Clause 4 gives Congress the authority over naturalization of people. So, there is no need to amend the Constitution, as with Article 5. Congress would only need to pass a bill or a resolution clarifying the intent of the framers of the 14th Amendment.
The Court ruled in the case of Wong Kim Ark that a child born in the U.S. of legal aliens,(not illegal aliens) was entitled to “birthright citizenship.” Same is true to legal U.S. citizens who have a child born outside the states. That child is a U.S. citizen, as is the case with John McCain, who was born in Panama to parents who were U.S. citizens.
The Supreme Court is not infallible. They have ruled incorrectly many times. They incorrectly legislated from the bench in their most recent decisions on ObamaCare and Gay Marriage to name a few.
Do you believe the framers of the 14th Amendment meant to give power and authority to illegal aliens to bestow US citizenship on the birth of their child simply by having the baby on U.S. soil?
I think not, because Congress passed The Indian Citizenship Act of 1924, wherein, it bestowed citizenship on all Native Americans born within the territorial limits of the country.