Sometimes the case, sometimes not so much, sometimes circumstances leave no choice but to own lots of choices, sometimes it ma work with one, and those criteria fit the defender as well. Shoot a smuggler outside of your farm or ranch, you might find his gang outside your walls later, and you may want a high cap semIautomatic rifle, and a superior power gun as well. that 9mm might as well stay on the nightstand. Shotguns or Enfield rifles,as well as grizzly bear killing handguns don't belong in a six story apartment building in heavy urban areas.
You are correct, and hit the salient points. Environment and skills are just as important as the others. Own a defensive handgun and train like Hell to face a break in that might turn very horrible.Own them all in case you out territory fifteen or even thirty miles from help, where your targets may start banging at you from the tree line, and practice like Hell if you want to be ready.
A few years ago an old lady was getting her mail and found a jaguar on her stoop.
OH, COME ON! Must EVERYBODY also keep animal sedatives and fresh meat on hand as well? I don't want to kill a jaguar whose only crime was walking through an unlocked gate, getting hungry, and finding someone who might feed it!
All we can do is learn probable scenarios, including those that involve literal armies, bears in the kitchen, and goons who want to steal the laptop and home entertainment centers. When we have to arm and train for those scenarios, hope for the best on the defender, hope for the worst on the aggressor.
It don't work sometimes. We've had vandalism and theft here for decades, over three thousand or more in losses. My wife finally talked me into spending several hundred dollars for motion detector security lights, and what happened? Some damned wankers came right up to my porch and stole hundreds of dollars worth of stone planters and statuary, then went into my closed patio and stole hundreds of dollars worth of power yard tools. I guess I should have invested in half a grand worth of cameras so I could at least have a witness! Instead, I just gave them lights to work by, and I'll bet that they are really grateful for that.