This is getting off topic (and maybe this whole thread should be forked and isolated) but is it explicitly (or implicitly) against any rules/moderation guidelines or just discouraged by the community? Don't get me wrong though, I don't care for them and I believe they do more harm than good. Just curious.
I don't think it's that at all. Pun threads generally make for very boring reading/discussion and tend to rise to the top because they're quick to digest, uncontroversial and mildly amusing. If you're looking for more substantial comments (arguably most HN users are) these can be a real chore to slog through.
You misspelt "people who like intelligent discussion". A joke now and then is okay, but try to give it enough redeeming value. (And for the rest, don't worry too much about downvotes.)
