You're wrong, as it can well be. Verbal bullying is in the tone and the language, as any HR Department would be able to tell you. There is absolutely no need for gratuitous rudeness, just make your point and move on. Correcting mis-information, as you say, is how we learn and is perfectly in order - if it's done in a reasoned and not overheated way. What is there to get so hot under the collar about, after all? It's an opinion - we are all entitled to them and don't need teddy flung in the corner to teach us the "error" of our ways.