Yeah that ascii art with three swastikas really added to the discourse. That and the second comment “your mom is Facebook” made me think the Algonquin round table had come back to life.
FWIW, showdead on HN does not surface a whole lot other than SPAM. Most of the difference here appears to be a defacto level of professionalism, which seems to be mostly enforced by politely telling people to not do silly things. For all the criticisms you could have about Hacker News and SV culture in general, I will give it one thing: It is definitely one of the most civil and best moderated communities on the internet that I'm aware of right now. That's actually more sad than anything, but it is what it is.