When I was young, such jobs were almost exclusively reserved for teenagers getting the first work experience. Adults were never expected to support a household on such wages. Now, it's just about impossible in any urban area. And if all the goof off young males suddenly decided to find such jobs, where would they be? Maybe if you booted out all the Mexicans they'd find work. When I moved to the city where I live now 30 years ago, almost all service jobs were held by blacks and few working class whites. Now most are Hispanic. Plus the influx of immigrants has raised housing costs tremendously. There is a finite supply of jobs that can be done by low-IQ/low-education people. Those jobs have been taken by illegal immigrants. We need to evict the illegals.
We also need to figure out ways to bring manufacturing jobs back to the US.
It's not simply "low IQ". That's neoliberal prejudice. There is a substantial portion of the population for whom sitting in a cubicle farm is just too unpleasant to contemplate as a career.
In addition, half the population has a below average IQ: what are they supposed to do? Starve? Sit on the dole their whole lives?
If they can't find work I'll tell you what they will do: vote for socialism.