Off topic: I would be curious to get statistics about the evolution of the ratio of downvotes/upvotes the past few years on HN. I also have the sentiment that HNers have been very "downvote-happy" lately, as you put it. I really think downvotes should be rationed in some way (and not just enabled after some karma threshold is reached).

My new habit: Automatically up-vote every greyed-out comment I encounter. I don't go searching for them, but when I see one, I upvote it without even reading it.

I used to read them carefully first, to decide whether I should up-vote. But from that experience, I've learned I almost always should -- the downvotes were rarely warranted, and almost always lazy and brainless. So I may as well save time and cut to the chase -- just upvote.

(If enough of us do this, maybe we can minimize the problem HN is seemingly unwilling and/or unable to address.)

That may well be true, but it isn't really relevant to the paradox. That's a second-order effect which needs to be established statistically, not the paradox itself which is pure graph theory. You're basically saying "You're more likely to be friends with people who make a lot of friends - that is an emergent property of a network. Also, I believe friendliness is correlated with success."