That’s because minds aren’t changed via facts. In fact I’m guessing most of the participants have doubled down on their views.
From the limited amount I’ve read, changing someone’s mind is a slow process that simply revolves around the person who’s trying to change the other persons views by asking questions that allows the person to question their beliefs and allowing them to find and explore facts from themselves.
I would have assumed that the only reliable way to change people's minds is to change their actual material conditions and the nature of their lives over an extended period of time. Though I suppose that is a form of 'allowing them to find and explore facts for themselves'. People have to experience those 'facts', not merely be told them.