The Founding Fathers were intelligent enough not to use the same term in two different ways in a single Bill of Rights, let alone in subsequent Articles.
As far as the “white male” interpretation, that’s fairly silly. Do you think they’d change the right of franchise back to only the land-owning class? No. That definition has been permanently changed/clarified through the amendment process. It would take an amendment to take away the right to vote from all individuals, and it would take an amendment to take away the right for all individuals to purchase firearms. That's what the case in DC is about (is a local law in violation of the US Constitution?) and why it has elevated to the USSC.
In order to determine the Founder's meaning, I went back to 1792 when we HAD a true, well regulated Militia. The Militia Act of 1792 said that members were adult, white, male citizens. Period. Set that aside for a second.
Now, the second anmendment protected "the people". Not "citizens", not "persons", not "individuals". "The people". In 1792, who were "the people"? They were "full" citizens with the right to vote -- adult, white, male, citizens. Their RKBA was protected by the second amendment.
So, using 1792 to determine the original meaning of the second amendment, it appears as though it was protecting members of a well regulated Militia. Or it's just a coincidence.
(Yes, today, "the people" include non-whites and women. But we don't have a militia we can compare that to.)