Gold is tangible and has a long history as money and a store of value becuase it is very durable and not easy to find. Most commodities are consumables, gold isnt really consumed. Gold is an insurance policy against fiat unstability, fraud and govt’s bad behavior.
Central banks and the IMF hold quite a bit of it. Why? Granted their not the best indictor of intellegence, but they do have a lot of power in this world. And they tend to control the quantity of “money” in the world.