We have different definitions of socializing. Commenting on a piece of news or opinions to enhance our thinking and gain knowledge/motivation/ideas, I don't call that socializing. I haven't made any connections through this platform and if I don't check the HNews for a week, I don't feel sad or missing anyone. But that's me. Someone else may be more (in)vested in here and consider HN as an integral part of their social life. I won't judge them.
I suppose there's a subtle viewpoint difference. You see yourself "commenting on a piece of news". I (and presumably GP) see you socializing with the GP, the way you could casually socialize with a stranger on a bus stop.
FWIW, meatspace doesn't maintain social graphs and push notifications - in physical-world social interactions, you're responsible for holding the social graph in your head. Just like on HN :).