Everyone feels this way about HN at some point, it is normal. It is probably true that the user base has grown and so you see more low-value comments in absolute numbers as time goes on, but I still think the overall quality is decent and the community moderation solid.

It is also a Friday afternoon, and HN's weekend (and to some extent overnight) 'personality' is noticeably different than during typical business hours. I enjoy coming here on weekends but it gets a bit more wacky.