Ah ... but even with that reasoning, the Founding Fathers _still_ wrote “the right of THE PEOPLE to keep and bear arms shall not be infringed”, not “the right of MILITIA MEMBERS ...”. Yes, Hamilton reasonably observed that trying to keep _everyone_ up to military par was nigh unto impossible, yet clearly the value of having _everyone_ at least part way there (to wit: armed and familiar therewith) is unquestionably useful to the security of a free state.
Oh, and before you go back on the old retread of “the people aren’t everyone”:
Using your reasoning that “the people” were just “white male citizen landholders”, that _still_ does not equate “the people” to “militia members only” as not everyone who could vote was capable of serving in the militia (to wit: old men).
Considering that various Constitutional challenges have been brought to expand who constitutes a recognized voter, “voters” now includes pretty much everyone except children, felons, and non-citizens - which means that if you equate “the people” to “eligible voters”, then the 2nd Amendment applies to pretty much everyone except children, felons, and non-citizens - or you have to give up your “the people means voters” reasoning.
Nor did they write, "the right of citizens to keep and bear arms", which is what you are implying it means.