Gold has a myriad of uses outside of it being a heavy rock. If it's price were to drop substantially it's use in industry would increase substantially and we know what happens to price when demand increases.
I don’t think industry is the floor you think it is. They’ll happily pay as little as they can for it.
I think the more honest measure is simply how many people have faith in it. Bitcoin and gold may be logically equivalent for this function, but a lot more people have a lot more faith in gold.
That's sort of my point. If Bitcoin and gold lose all financial value, at least with gold you have a heavy rock and to most humans, visually appealing. You can do something with that - build a house with enough of it, make jewelry out of it, forge weapons (would they be any good?)
You can't do anything with Bitcoin if is exchanging at $0 USD.
If gold loses its value, then it's just a heavy rock. They both take time, money, and resources to mine but neither of them have any intrinsic value.