When you discuss something, you act with respect toward the other participants in the discussion. Discussion makes me feel like this:
This is Zinashi thoughtfully considering a sandwich, but you can easily imagine she is considering your point of view.
When you remove respect from your discussion, it becomes an argument, or worse, an attack. This is how I feel about that:
I like to read a variety of things to keep myself informed, and it really troubles me that so many people feel comfortable being disrespectful to others on message boards and in comment spaces elsewhere. If you'd like to inform someone of something they do not know, or ask a question seeking clarification, you don't need to do it with an air of superiority in your post or the ring of judgment in your assessment. Approach one another with gentleness. It is possible to be firm and kind at the same time. Let's work on that, internet.