Respectfully, this is nonsense.
Just off the top, there must many incentives that can be removed, eg. welfare, medical care, making it a fed crime for businesses to hire illegals, making it a felony to vote, or to abet voting illegally (thus disqualifying any chance of citizenship), making it a deportable offense to drive without insurance, etc.
The VALUE of being here is rising sharply. That’s the REAL incentive. We’re destroying the Mexican economy and making dollars worth greatly more. People will take the risk to come because there will be no alternative.