Earlier quoted context omitted.
bcherny is saying that karma's primary function is content curation. sure, you might like a few downvoted submissions from time to time, but for most content karma scores will be saving you time sifting through a sea of content. removing content by hand requires an active and vigilant moderation team, user votes help mitigate that burden. Also, the power to 'delete' is most likely a slippery slope...
I see a lot of great content here greyed out. Including some of my own! At the end of the day, I'm not happy to follow the collective judgment of other users.
It would be nice if HN would allow sorting of threads by various filters, such as time of last reply, and/or decide whether or not low-sorted comments get greyed out.