Doesn't seem worse than Reddit or Facebook to me. Heck, even though it isn't as obvious the amount of negativity on HN about everything Chinese is basically the same racism, just written in ways to avoid getting removed.
Did you visit the site? They have multiple boards on the sidebar that are explicitly dedicated to racism. One of them is just named “[Nig]s”. There’s a picture in the sean one with a 1488 behind pixel black people.
I cant be racist - some of my best friends are blacks.