I think one thing positive is that watching the debates with flat-earthers (and other beliefs) is that you learn a lot about logical fallacies and how they are employed to win arguments. I recently saw a debate between an (alleged) scientist and a flat-earther and the scientist didn't do so well because he seemed unable to deal with the tactics that came his way including the use of logical fallacies.

The way these fallacies are employed is one of the reasons I think at least 50% don't believe in flat earth themselves and are just trying to get attention.