It might be interesting to address the longevity of Reality TV through the reasons for its popularity. What aspects or characteristics about Reality TV make it so popular. Why do we keep on watching? You could address some main reasons like:
1)The average viewer feels that they can identify with the people on the show; there's a sense of ethos--the characters are relevant.
2)Shock value-- Who doesn't love seeing people behaving at their worst? In a show like Dance Moms or Jersey Shore, even (and I think that it would be a good idea to cite current shows to support your argument), viewers can escape from their own problems and enjoy seeing the disfunctionality of other people's lives or families (the Kardashians.) It's life unscripted. Anything could happen.
As for problems with the genre, some of the problematic areas are exactly what make it so popular to begin with! For shows that are touted as 'Reality TV,' often times the situations couldn't be farther from. The producers intentionally choose situations and people for their high-interest level, not necessarily because they are grounded in reality. In shows like Survivor or even MTV's Road Rules or Real Housewives series, are any of those shows reflective of reality? Sure, they have real people in them. Sort of.
This is a great essay topic, and I would be sure frame my thesis around the connection or correlation between the explosive popularity of reality tv, it's longevity thus far and the reasons why so many people are addicted to it.