Would it be ethical for a doctor to change his last name to a Jewish sounding name in order to attract more patients?
A doctor who changes his last name to a Jewish sounding name in order to attract more patients is taking advantage of stereotypes about Jews and doctors in order to be more successful. This tends to reinforces the stereotype (unless this doctor is obviously a terrible doctor). And it thereby increases any prejudice against non-Jewish doctors. This is one reason why the change of name is, in my opinion, unethical. It is also unethical because it is deliberately deceptive (even though it does not involve the explicit telling of a lie). Physicians are held to high standards of truth telling because they are in positions of trust.