What naturalized citizens? At the time of our founding, there were no naturalized citizens. The US had no natualization process in place yet the day the constitution was adopted.
They had the forethought to empower Congress with the authority to set up a Naturalization process.
Don’t get cute, we can not claim the Founders had infinite wisdom in one breath, and then claim they were too stupid to think we might need some type of way to make someone a citizen who was not a Citizen at birth a Naturalized citizen.