A large fraction of the harm from firearms comes from their ability to fire rapidly which didn’t exist when the constitution was written. As such it was making a very different balance of risk between the general public and individuals.
The right to a jury trial is another example of favoring the individual instead of say, the Star Chamber: https://en.wikipedia.org/wiki/Star_Chamber
I don’t think we even disagree per se, but it’s hard to argue the constitution wasn’t written primarily with the thought of what England and how it exercised authority in mind. Individual roadmen and ruffians, let’s say, existed but weren’t existential threats to shape the tone of the new nation’s foundation, were they?
The degree of importance they place on individual factors here is obviously debatable, but they just had two governments fail. England and the articles of confederation didn’t work so there was a larger emphasis on practicality over idealism.