If mind-changing means coming to believe something opposite what I formerly believed, although it has happened in my life, I don't recall that happening here. If it means modifying my opinions, then yes, it has happened here, and other places on the net.

Whenever someone realizes that "I don't understand, would you explain" is not a rhetorical question, or talks about why they believe what they do, I learn something. The world becomes less black and white, more gray.

In "real life," when you start a conversation about a contoversial subject, it's quite likely everyone more or less agrees with you, because you discuss these things with your friends. If you discuss them with strangers, you often wind up yelling and calling each other names. We have a fairly wide range of opinions on any issue here, and folks normally take the time to explain their opinions. I've learned much from those discussions.