Well, I prefer African-descent, European-descent etc. when referring to ethnic distinctions. Just my personal preference. Well, these shows have very little to do with the cultures of the said ethnicity's origin countries, but rather the culture of the country of show's origin e.g. British. Yes, it is not the source of information for ethnic representation but pop-culture does create an impression in a typical consumer's mind regardless of if they are interested in the demographics of nations or not.