The California gold rush. This was an actual, legit thing where there were more people trying to score bigtime selling supplies to prospectors and miners than there were prospectors and miners trying to score bigtime with striking gold.

During the "Gold Rush" era (Wild West 1800s), there were plenty of people descending onto California to try and make their fortunes by staking out land to mine and pan for gold.

However, the first millionaire wasn't anyone who got lucky staking out a mine. It was the largest store owner in the area selling all these prospective miners their shovels to dig with.

The "AI industry" has a lot of parallels here, but everyone wants to be the store owner, and hardly anyone has a genuine need for their tools.