Someone explained magazines to me a decade ago as discovering stuff you don't know you don't know about. That's the value of HN.

I also find that keeping up with the news on the regular basis is a waste of time and it's mostly regurgitations of the same, but when I tried cutting it completely, I find that in a couple of months I am completely out of the loop and it takes quite some time to catch up.

This is not a useful example, but it's a funny one. I was out of the country and away from tech for 3 months and when I opened my door on returning to the US, the delivery guy was a teenager, and says "Man, you have so many good Pokemon in your yard!". I had NO idea what he was talking about and said "Oh, cool". Found out Pokemon Go was a thing a few weeks later.