Not untrue, but it's one of the less bad places to come on the web.
It can also be to do with your own mental filter... HN has submissions that are both on the pessimistic doomsday side at one end and hyper over optimistic side at the other end, but orthogonally there are also purely fun submissions - and these can be quite uplifting, a happy reminder to many of us of why we originally ended up doing what we do.