I thought I was going out of my way to not be insulting. It has absolutely nothing to do with feeling superior. It has everything to do with the fact that I frequently encounter people who surprisingly don't seem to know things like this, and I wish for them to learn so they can avoid the mistake in the future.

I did not engage in the discussion because I had nothing further to contribute to it. I recognized that, and contributed what I could entirely orthogonal to that.