That's not what he meant. Gold's value as a material is pennies on the dollar for gold as an investment. When people talk about 'value' of gold, they're referring to its use as a 'store of value'.
Yeah, but that isn't why it's worth what it's worth.
Good point.. but that doesn't make it a productive asset. A productive asset is something that produces an output--ie: something that generates an income for the owner of the asset. If I own a farm, the farm produces crops that can be sold.