Well, no, not according to the Fourteenth Amendment as it is written, no, he isn't an American citizen. It's been misapplied in contemporary times such that this guy and others like him can claim citizenship by their illegal-sneaking process, but it does not mean that the Amendment ever meant that.
Most people get that the process of illegals sneaking in for purposes of birthing at taxpayer expense is usery of the worst kind.
Whether it's "legal" or not -- the point is that it's not ethical behavior and it certainly is objectionable.
Let this offensive guy enjoy his old age in a country he subjects to Mexico but eventually the Fourteenth Amendment will again be accurately and appropriately applied and people such as this can go back where they belong. It isn't in the U.S.
He doesn't deserve that American flag. Let him paint his house with a Mexican flag but he doesn't deserve that American flag.
Hold on for a second. Who says you get to decided when something is misapplied or not? I don't agree that it's misapplied, and I doubt the Supreme Court would agree either. Sorry, but I'm not conceding citizenship as a birthright is a misapplication at all.