The problem with text only communication is that no body language, facial expressions or tone of voice comes across. It would look strange if someone posted "I believe you are wrong," he said with a warm smile. Or "I believe you are wrong," he retorted with a snarl. Perhaps that's why these were invented >> http://smiley.cool/en/emoticons.php
But confrontation is often only in the 'eye' of the beholder. Some people would be best posting somewhere no one can reply, because some consider it to be rude or even nasty if anyone dares to have a differing opinion. It seems to come as a shock to them.