I don't really agree. You can be "shouted down" in text format, even if not literally. And yeah it's not about reaching the unreasonable person, but it's about not letting them win at the game they're playing. Like I said, responding to aggression with reason can come across as weakness, and for some people, they'd rather feel strong than feel reasonable. It's not really as simple as the more reasonable person wins, there's a range of different things that are going to influence who people agree with, it might be aesthetics and which side sounds more cringe, or it might be empathy, or so on. "Logos" is only one factor.