One of the indications the signals we perceive automatically regarding whether an idea is “truthy” is that something is either prevalent, common, worthy of considerations (2 sides), laughable, stupid, immoral.

Balkanized feed driven experience can help expose people to erroneous signals eg seeing pro flat earth things constantly because it was selected to be like previously engaging content and confusing that with it being commonly believed.

Treating an idea seriously in other venues only makes this signal problem worse not better. If they were capable of reasoned argument they wouldn’t be flat earthers to start with the only thing between them metaphorically or perhaps literally shoving pancakes up their ass is the type of social signals they are getting. I believe that ridicule is a net positive in deterring stupid beliefs because it deters SOME folks from believing whereas respectful argument is virtually worthless again when dealing with such folks.

Consider the same flat earther is all over the net speaking the same nonsense hundreds of times per year. Nonsense and ridicule is seen by hundred or thousands of folks whereas everyone is still talking to the one asshole. It’s pretty easy to see why it ought to be a net positive.