If they're worth more than their industrial applications, how can it be economical to use them for their industrial applications?
If gold-plated contacts cost more than they're worth, nobody would make any as it would have a negative ROI.
I agree that the market cap of gold is higher than it would be if industrial applications were the only source of demand. But given that gold is used for industrial applications, it must not cost more than it is worth for those applications. Hope that makes sense.