Strawman argument.
How many agents does it take to serve a Hormel/Tyson/Libby/Cargill plant manager with a federal cease and desist order, a federal felony warrant, and a federal search warrant. Followed by two private lawyers representing the plaintiffs of a public class action RICO lawsuit against that plant?
I count 10 people maximum, and that plant will be absent of illegal aliens within 30 minutes.
It is not realistic what you propose. It’s just not. If you are not willing to cut benefits that may be available, they won’t stay out if you even are able to find and process all of them and manage to find conservative judges who won’t let them off.
There aren’t enough resources.
Turn off the tap and let’s look at a much smaller and more restricted welfare program.