First, copper is a better conductor than gold (~16 nOhms/m vs. ~24nOhms/m, lower is better). Gold is primarily used as plating because it doesn't corrode. But that doesn't really impact the value of your question.
When a core material like gold changes price, the impact to the consumer depends on the rate and absolute value of the price changes.
If the total impact to the product's price is small or sudden, then it is either passed on to the customer or absorbed by the manufacturer. There isn't a lot of gold in a typical consumer product, for example, but there is enough to make a wild swing in gold prices noticeable to the supply/operations groups.
If the price increase is really large or forecast to take place over an entire product development cycle, then the designers will take a long look at the tradeoffs and decide if they want to make a cheaper product or a more expensive product.