Incorrect! The high priest Aaron was not a Jew neither was he a gentile, he was a levite. Moses was not a Jew, he was not a gentile either, he was also a levite. Jews come from the tribe of Judah. There are 12 other tribes in Israel that your false statement wrongly gives the label of gentile too. A gentile is somebody of the nation's, a gentile is somebody not grafted into Israel. A gentile is somebody not in Covenant with God. If you claim to be a gentile then you are claiming to not be in Covenant with God.
RE: Why do you say it's wrong to identify as a Gentile?