The responder is never actually confused, they have a question that they should just ask.
1 me being polite and not calling you an idiot.
2 me hedging my bets in case I am the idiot.
> I think you're wrong
> Here's why I think you're wrong
> Please correct me if I've misunderstood something
It divides fairly evenly (I think, being generous to myself here) between:
Yep, something I thought was true was not true.
Something they said was wrong, or they omitted something without which their meaning was ambiguous.
Maybe a smattering of "I/they misparsed what was said" too. But really. Often I'm just confused. When I use it I definitely don't mean they're an idiot I just worry that they'll think I'm an idiot... (...and that they might be right.)
Maybe it's just what happens when narcissists get online. The inability to acknowledge that the argument doesn't matter and so you can chill out and let retards be retards is fundamentally a failure in humility.
is another example but I think there may be some expression of non-understanding. "So retarted it doesnt make sense."
Similar, "are you a n*zi" never seen here but as a simple but clever "Could you elaborate?" often as a reply to a polite but ambiguous comment. It's basically bait for the ambiguous commenter to confirm or deny the morality of their comment.
Of course, people will inevitably use it sarcastically.