There are a lot of things that influence the debate we typically see. Most people lack critical thinking skills, the tools to comprehend and analyze an argument. Many people don't know the difference between mean and median, and are much less able to understand a comprehensive statistical analysis; in other words, they have no idea if a certain data set is meaningful. Another factor is emotion and general bias. Even worse is that the media has to pander to the lowest common denominator. So the segments you see on TV are vapid exchanges. I don't know if that is the cause but I've noticed people in everyday life tend to mimic this TV show style argument. This style consist of each side barraging each other with stats and anecdotes that aren't statistically meaningful.
As someone with a STEM background and a gun proponent, the most difficult things to overcome in the debate are most opponents are 1) ignorant of firearms in general and 2) lack the education to form a substantive argument. It's like arguing about platinum catalyst layers in a fuel cell with someone who think batteries are witchcraft. You cannot win an argument with someone unable to comprehend it. Some anti gunners are intelligent but I've yet to see an argument worth much.