And, ironically, even interestingness can get repetitive. When I see a post titled "How I made Netflix' video decoding on Android 25% faster", I know that I'm going to find a war story where some silly hardware bug was preventing proper cache management or something. It's interesting in a way, and if I read the full post I'm going to learn plenty of new things – but at the end of the day, I've seen (and done) it all before. Not this particular bug of course, but this type of story.
What I'm really looking for is ideas and thoughts that are completely new to me. Not just in their particulars, but in their general direction. That's very difficult to find. And "dissenting", "controversial", and "offensive" opinions are an absolutely crucial part of finding it, in my experience. A "sort by controversial" feature like Reddit has would be a godsend for HN.