I strongly agree that proper parenting would be most beneficial. However, good parenting frequently is absent. We have all seen parents that are incapable of believing that their child would do anything wrong, so there is nothing to correct. There are also plenty of parents who live vicariously through their kids and pressure them to do anything to win. I know of a parent who also runs an "academy" and teaches his students to use their body to block the opponents view of the ball when running for a lob, and call it out regardless of the truth. He says that if they can't see it, they can't argue.
I say the USTA should step in and make a policy that tracks habitual cheaters and imposes progressively more harsh punishments for repeated occurrences. Right now the slate is cleaned after every event. You can cheat your A _ _ off and not be at risk in the next event.
If they had a running chart of over-rules and during the course of a year a player would be suspended for increasingly longer periods as they accrue more "points" they would stop. Referees need only track who got overruled in an event and enter it into a back-end program for tournament directors at the conclusion of the event. A computer will issue suspensions automatically and their entries for future events will be rejected until the suspension is complete. No human interaction needed, so the ref doesn't have to deal with the antagonistic parent.
To avoid penalizing kids for true accidental "bad" calls, it could allow for 2-3 over the course of an event before it began to count against the kid. I mean really.. who has more than three overrules in an event unless they really are cheating? I think my player has been overruled twice in the past 12-months which amounts to more than 25 tournaments, or 100+ matches.
Think of it like driving. You get points attached to your driving record for various infractions, and you are penalized by higher insurance rates, suspension, and even revocation if you accrue enough points. If I could speed with no lasting ill-effects, I'd do it more often.
Kids who cheat aren't taught that there are consequences for their actions... except that they win by doing it. Give them some negative reinforcement and they will have to adjust their behavior.