Earlier quoted context omitted.
Because the unemployment rate is a lie. It is denominated by the "labor force", which, if one excludes those who are no longer seeking work or chronically unemployed, it's basically being dishonest with statistics. One does not have to feign ignorance as to why there is a disconnect between the statistics and the reality.
It's not a lie, it's a technical measure that people misinterpret. If it was a lie you'd expect suppression of the further data. https://www.bls.gov/news.release/empsit.t15.htm
Creating a measurement that gets blasted on the front page of news that is largely misinterpreted, while keeping the actual figures out of public view enough so that only a small fraction of the population sees it seems to not be too different from a lie.