I saw the offending comment as well. The comment was made by the original poster in response to one of your responses. It was unfortunate and I was ambivalent about it. I thought it was rude. Not only that, it extinguished any further comments. I was following the thread and was tempted to participate before things turned rude. The thread just died.
As I age, one of the things that I've been working on is trying to put myself in another's shoes and understand what would motivate someone's actions or words. It's always easier when I'm not the target!
One possible explanation for the rudeness could be the very condition that we all struggle with: high, low, and overly variable blood glucose. I've made those kind of rude comments in the past and after the fact saw that bad BGs played a role. I'm not excusing rude behavior, just trying to provide a possible context to perhaps understand it.
I admired your response to the rudeness in question; it was measured and not over the top. I also could see what prompted the outburst. Sometimes these communication snafu's just happen. Especially in the two dimensional anonymous quality of this medium.
I'm sure the person in question has some regret about the exchange. Apologies can serve as a great way to heal the rupture but waiting for one is usually unrealistic. Live and learn, it's best just to move on...