It’s weird because Switzerland is one of the most armed countries in Europe, as in they have firearms but barely any shootings of any kind (so you don’t often hear news equivalent to a guy shooting students in a classroom or killing people at a shopping mall over there). Part of it has to do with the draft (most people who purchase firearms have a form of training, as they learnt how to properly handle them during military service).
One reason I haven’t seen mentioned yet is practicability.
Yes, people have the tools. But how do you get that tool to where you need it?
In the US I believe you can just carry weapons for whatever reason you want. That’s not quite the case in Switzerland. If you’ve got a gun for military service, for example, you’re only allowed to carry it from and to military service or the shooting range. You can’t just go to a school with it. Same applies to other purposes. You can only carry a gun for the specific purpose you have your permit for. You can’t just take it to a school or mall.
Plus, the people who have guns at home usually only have the guns, no ammo, iirc.
I can only comment about what goes on in the US. In many states you cannot just carry the guns wherever you want. In states that allow you to carry a gun that’s concealed, you will need a special permit. Some states don’t require this though. If you are carrying in the open, some states allow this, but many don’t. There are also rules about where you can take the gun. For example, many states do not allow you to bring it on school property.
In California you very very rarely see anyone with a gun. In some red states it’s pretty common.
The issue is easy access to guns with ammo and the culture behind them.