1. Blizzard has their name / track record to stand behind.
2. derpmeister has a month-old HN account, which is backed up by/linked to nothing else.
3. (for example) If Linus Torvalds had posted what derpmeister had, I would be more inclined to take it at face value.
4. derpmeister's post automatically takes itself into 'troll' territory by starting off with the 'Blizzard apologist' comments. This makes the anecdote seem less believable without anything else to back it up.