These remind me of the “I don’t dial 911, I dial .357” and “Beware of dog. He eats everything I shoot” type signs. They bring a smile to my face but I would never put one up outside my home.
If someone in my family did use a firearm in self defense I fear the sign would be used in either criminal charges or a civil lawsuit to indicate we were looking for an opportunity to shoot someone and perhaps were just a little “too enthusiastic” about defending ourselves.
It also is an indicator there are guns inside the house which are “available for the taking” when no one is home.