Gold is a worse conductor than copper, a much more common metal. There are many metals that are more malleable. Dentistry has moved away from gold and is typically only used for aesthetics. In electronics gold is mostly used to resist corrosion and it’s typically electroplated to do so, because of this the amount of gold use is incredibly small. Finally, almost every metal protects against radiation, hell even skin does that to most radiation and where that differs is in ionizing radiation where most of the time lead is easier to use than gold.