What doesn’t work with your comparison with fire extinguishers and seat belts is that there’s no drawbacks to them and there’s no alternative permanent solution (except public transit, but even there seatbelts wouldn’t be a bad thing to have). People also go without both for all their lives so we’re very far from food, love, water and so on.
Right now you’re arguing guns are a necessity like you were saying fire extinguishers are a necessity because of pyromaniacs or seatbelts are necessary because of people who commit suicide by car crash, two statistically insignificant events, so insignificant that if they were the only reason things caught on fire/people died in car crashes, neither fire extinguishers or seatbelts would exist. The way you interpret statistics I bet your retirement plan is to win the lottery!
It’s ok you lived a traumatic event that shaped your vision of the world, what your need isn’t a gun, it’s too see a psychologist, just like the world you live in, it doesn’t need more weapons, it needs more social support so people don’t want to own weapons.
And yes, clothings are worn by people all over the world even in climates where people could go naked at all times and are at the base of the pyramid of needs.