I agree with the point, but this isn’t a perfect metric.

There are cases where productivity stagnates or drops due to choosing to use low-paid manual labour over automation, etc.

If you look at figures outside the US this is more prevalent (e.g. the UK carwashes - https://www.theguardian.com/commentisfree/2023/mar/14/exploited-workers-britain-hand-carwash-licensing )