Uh, that's a thread that asks "what's your most offensive joke". Using that as evidence for anti-semetism is like using Wikipedia's inclusion of Nazi emblems on their page on Nazism to prove that Wikipedia is anti-semetic.
My reply was not meant to assert that redditors are actually anti-semitic in a nazi sense, but to show that it's not really "equal-opportunity". In short, jokes about jews and blacks are clearly acceptable and even popular but gay jokes are not.
Maybe one could claim that gay jokes aren't there because they aren't considered "most offensive" to start with but I really doubt it. I think it's just a code for "let's make racist jokes".
I'd say racist jokes (and the dead baby ones also found on that page) tend to be considered more offensive than most other categories. I'm trying to think of gay jokes more offensive than the ones posted in there and am coming up short.
