Yes. Hardness minerals form scale inside water heaters, dishwashers, washing machines, faucets, and other water-using equipment. That buildup can restrict water flow, coat heating elements, reduce efficiency, and contribute to premature repairs.
A properly sized water softener removes calcium and magnesium before they circulate through your home. This cannot guarantee that an appliance will never fail, but it can reduce one of the leading sources of mineral buildup and unnecessary wear.