Keep in mind that people don't talk about that which they believe they completely understand. When someone reaches a satisfiable conclusion in understanding, they lose interest in the subject and move on to something else.

The political discourse around polarizing topics isn't disastrous. It takes place exactly because people realize that they are complex issues not fully understood, and are talking about it in hopes that more information will come to light to help them reach a greater understanding. This is why the more complex the issue, the more it will keep coming up over and over.