I believe that many don't understand "debate" in the context of how it's formally used. It isn't about the topic but instead about the presentation of the arguments. How is the topic addressed, are valid arguments and rebuttals provided, and is supportive documentation for the arguments offered.
We could take an example of the Earth revolving around the sun for example. While we all know that the Earth revolves around the sun if the proponent of that fails to establish evidence that the Earth is revolving around the sun while the opponent demonstates that the sun rises in the East and sets in the West then the opponent would win the debate.
The moderators are working on judging criteria based upon formal debate and we will share that once we hammer out some of the details. In the end the topic itself shouldn't really matter and certainly the debate itself cannot be judges based upon the topic but instead on how the members address the topic in the debate. The best debates often require the participants to switch sides in the middle but that might be too challenging for most.
Republicans were more likely than Democrats to express racial prejudice in the questions measuring explicit (anti-black) racism (79% among Republicans compared with 32% among Democrats).
Source: 2012 AP Study on racial prejudice in America (link providee on request by PM)