The US unemployment rate measure is deceptive
qz.com
qz.com
Beyond the unemployed there are separate numbers published by BLS for those not in the labor force. This number is at about 95 Million.
Who is not in the labor force? https://www.bls.gov/cps/cps_htgm.htm#nilf
The numbers https://www.bls.gov/news.release/empsit.t01.htm
In the last decade, total compensation has risen drastically while income has not. If you only measure income, then it will appear as though the lowest paid fulltime workers did not see as great of gains as the highest-paid workers, when in fact the difference is much smaller when you include health benefits.
So, income is an example of a consistently-measured metric that does not really corelate with the attribute that most people would care about (total compensation) and thus does not act as a good proxy for the measured attribute.
As a side note, the increase in income inequality is not "much smaller" when benefits are included. See for example https://ourworldindata.org/incomes-across-the-distribution/. The gap is almost entirely due to soaring executive compensation, and since there is no correlation between performance and executive compensation (some studies even show an inverse correlation: https://cooleypubco.com/2016/07/25/new-study-shows-inverse-c...), any natural brake on the spiraling salaries seems to have failed.
Another way that the number is fudged is that those who are eligible to work under DAPA are not counted in the population until/unless they are employed (in an actual W-2 or 1099 job).
This is opposed to the old use 'transient unemployment' which means the amount of people who do not currently have a job, perhaps because they are searching.