Post #1: Comment using the N word
Post #2: Someone using "fag" to insult people who, presumably, use Arch linux. (The term was Archfags)
Post #3: In response to something about headphones: "that deaf faggot [n-word]"
So it's funny. I've been browsing 4chan for 5 minutes and couldn't avoid racism & homophobia in the very first things I saw. Maybe you should actually visit the site instead of just spreading misinformation.
If you find that hard to understand, maybe stay away from HN where we try to have at least some minimum of reason in our discussions: you either lack that by minimizing racism and hatred to "bad words" or you are a troll arguing in bad faith.
You mentioned /g/ -- there is a daily programming thread on that board with a very long history. I've seen some really interesting projects posted there. Some even made their way here eventually. SerenityOS for example.
it's offensive to outsiders....to keep them out lol
It's definitely there. Not in /pol/, but /pol/ is a subset of 4chan.