You're right that what that user did was not ok. Unfortunately comments like this one just compound the problem. When you can't flag a comment, someone else probably will. Or you can email us at hn@ycombinator.com. But please resist getting into a personal spat.
Everyone in this thread was at fault. You can't post things like "Did it blow your mind when you understood something for a change" here. HN's rules hold regardless of how provocative someone else may have been.
We all lose it on the internet sometimes. On HN the thing to do is recognize that you broke the rules, stop blaming the other person for it, and move on.
The I-merely defense ("I was merely X-ing, but they were Y-ing") doesn't work. You can, and people do, justify anything that way.
You're right that what that user did was not ok. Unfortunately comments like this one just compound the problem. When you can't flag a comment, someone else probably will. Or you can email us at hn@ycombinator.com. But please resist getting into a personal spat.