To be honest, it's been like this for a long time. If you haven't noticed the negativity, you've been reading a different "hacker's news" than everyone else on the internet.
To be fair, I've been a regular user under this account for 6 years now, and before that would visit frequently. I know there's always been that component to this place (it's a site publicly available on the web, it's inevitable) but it seems like there has been, maybe just through my perception, a strong rise in the ratio of valid criticism/complaints and seemingly spiteful comments that don't seem to want to accomplish anything other than to incite anger. I have always really appreciated the discussions around here!