If “natural born citizen” is synonomous with “natural born subject,” then no exception is needed for Thomas Paine.
All those who were citizens at the time the Constitution was adopted had parents who were not US citizens, nor were any of them born on US soil, because the US didn’t exist until then! It was created by adoption of the Constitution! So everyone was a naturalized citizen.
So again, you are refuted.
No where did I state that a natural born subject of Britain automatically becomes a natural born citizen of the United States. The concept however, did carry over, as codified in Wong Kim Ark.
But men like Paine who were born in England and who didn't become a citizen of the colony until 1775 were eligible.