How did you know that XorNot replied to your previous comment?
Notifications, addictive design and gamification are really bad practices that we should try to avoid - but the underlying drug of social media is that someone noticed and reacted to your content, and HN provides that just like Facebook or Twitter.
I think all three of you are actually hitting the nail on the head. Large headed nail I suppose ;) Take ne as an example. I could've had a really low user number on Slashdot if I had registered right away. I never actually did but I read Slashdot for many many many years.
I turn off notifications on my phone for almost any app. It's just way too annoying. I'll get to it when I get to it! I guess I'm part of that minority mentioned above but as you say I do keep coming back too. It's not black and white but we can stay on the healthy side.
If I try to find an analogy, it's the difference between sitting by the fire in the evening and chatting with other people vs. spending the entire day running around listening to and actively spreading rumors.
If you disable the notifications, that's good for you. But you're a small exceptional minority.
HN afaik has no such feature at all.