I think the reason they didn’t put in a two parent requirement was because at that time the wife took her husband’s citizenship at marriage and was irrelevant in determining citizenship of her children.
I agree. I've been making that point. The mother's citizenship is (was) derived from the husband and so it means nothing, but no child has more than one father (well, used to be so). As "citizen fathers" was the usual phrase, clearly it derives from the plural children, and the two-citizen-parents claim would need some modernization before it could be applied. Based on the laws enacted since women gained full citizen status, it has become a case of either parent rather than the father, and not both parents rather than the father. But to decide it either way requires a law made by Congress, which opponents of either outcome would protest. Only one way to make it absolutely decided, and that is with a constitutional amendment, but there are still people delegitimizing the 14th and the 17th Amendments, among others, so it never would end, IMO.