I disagree that it’s a serious problem.
It’s first of all a supply demand problem. If the demand for their labor stopped, illegals would stop coming. Simple as that. And rather like the drug “problem”.
How many “got away”. That’s one of those ambiguous fill in the blank with your fears questions beloved on the Right and the Left. We actually have a good sense of the actual numbers in the country, but the Right would far rather pretend that the border numbers you related weren’t caught at all, because the border is open don’t you know.
So the actual problem is what? Illegals are employed but underpaid and with few rights. That is a major problem for them but not the citizens who take advantage of the cheaper prices they can get for their services. Illegals DO pay taxes in that taxes are taken from their pay (even though illegals may never file a return) for the simple reason that while hiring an illegal gets a company a slap in the hand, avoiding payroll taxes gets a company a firm kick in the nuts. Illegals might use some government services, such as they are, but they are productive members of the community.
No. The only major problem is the actual cynically invented Rightwing problem that they are replacing white people and something called white culture. Which they are not.