my rigorous attitude towards his arguments

You suggested that I likely haven't spend 5 minutes thinking about the subject which shows complete ignorance. That might be a honest belief but it certainly not rigorous.

Everybody regular of LW has thought about how to improve LW for more than 5 minutes. In my case I have even written tons of posts about the subject.

There are two ways to read this.
(1) You felt personally attacked and wanted to retaliate.
(2) You lack basic understanding.

It's very hard to read what you wrote and not come to the conclusion that (1) played at least a part.

I wanted to show open palms or something, but I cannot do that on keyboard.

And you failed. You communicated in a way that doesn't signal what you want to signal.