That's the same tried and tested argument that always comes up every time unemployment is discussed. See f.e https://news.ycombinator.com/item?id=17474163

But it is completely false as this graph shows: https://www.bls.gov/opub/ted/2018/u-3-unemployment-rate-was-... Empirical data suggests that U6 is almost linearly dependent on U3, meaning that, indeed, the "real" unemployment in the US is record low.

Yes, service jobs doesn't pay well. That is perhaps related to decades of union busting and resistance against raising minimum wages?