Some people have never been in a situation that required one, and they don’t understand why people would need one.

Realistically such situations come about because of easy access to guns. Make it more work to buy and keep a firearm, use red flag laws to prevent those who cannot safely own and maintain a firearm from having them, provide easy gun buyback & disposal, and eventually the gun population will dwindle and fewer people will have actual needs for guns. Overtime with such programs firearm ownership should eventually find itself at a reasonable level where only responsible gun owners have them