It would be one thing if lower class Americans actually went for those jobs but they just straight up don’t [at the current low wages paid].

FIFY

At a high enough wage these jobs would be filled - but with 20 million illegals able and willing to work for less, there is no pressure upwards on wages

Unsure if you're ignorant or simply disengenous.

Also, if you really were concerned about lower class Americans, you’d think building an immensely expensive wall would fuck up the economy a lot more than people coming into the country to take jobs that absolutely no one wants for pennies on the dollar.

So expensive.

In fiscal year 2014, the U.S. government allocated the following amounts for aid: Total economic and military assistance: $43.10 billion

From Wikipedia.

And since illegals are a massive burden on welfare, education costs, crime and damage against the citizenry, having their numbers reduced would more than provide enough savings for 10 walls.

Illegal immigrant families received nearly $1.3 billion in Los Angeles County welfare money during 2015 and 2016, nearly one-​quarter of the amount spent on the county’s entire needy population, according to data obtained by Fox News.

The data was obtained from the county Department of Public Social Services -- which is responsible for doling out the benefits -- and gives a snapshot of the financial costs associated with sanctuary and related policies.

Just one city.

You're pretty ignorant - or more likely, a disengenous propagandist