Sometimes the truth hurts. I think we're all mature enough to handle that. And I personally prefer when people are blunt/honest instead of sugar coating everything or refusing to state their opinion because they're afraid it will offend. There's nothing more annoying than someone who's too weak to speak up and tell the truth -- they can do just as much harm as the people who are mean.
For what it's worth, I just re-read the top 5 comments on the post he's referring to and couldn't find a single one that was mean. Negative, sure, but mean and negative are entirely different things.
> And why are you making the arrogant assumptions that we want to invest our time and energy in reading your comment too?
Well if that's not the definition of irony right there...