But the market cap of gold is vastly more. What you're saying is that the market cap for shovels would be the upper bound of the real number we are looking for, as there are other uses. So we can simply be more sure that gold has returned more economic value to those who obtained it than those who created shovels.

The truth is, what I said doesnt make any sense at all. I never thought it did. But thinking about it for a few seconds makes it obvious that it's unlikely selling shovels is actually a better business than digging gold. The major gas companies make more money than the companies who build rigs. Selling shovels is a lower variance method of capitalizing off a gold rush. I prefer to do both.

Most every successful startup is essentially someone digging for gold in a new gold rush. Rarely are they selling shovels.

Digging for gold or oil is kind of a misnomer as the important thing in both cases would be owning land with the appropriate land rights.

The common saying is misleading. It should be, "you're unlikely to lose your shirt, will have a higher likelihood of success and stability, and an overall easier time selling shovels in a gold rush, but with lower overall gain than the outlier winner gold miners" but that doesnt quite roll off the tongue.