You hit the nail on the head. There is a large amount of astroturfing that takes place in HN. And the mods carry water for them. I am shocked that you don’t have them looking down their nose at you with their typical aplomb.
From all that work, experience, and data, I've learned how utterly misplaced these cheap claims about astroturfing and manipulation usually are. They mostly have nothing to do with reality. What's going on is that when people encounter views they dislike, they get upset and reach for explanations of abuse, bad faith, manipulation, disingenuousness, etc. as a way to ward them off. People on all sides of every issue do this. It's against the spirit of HN, which is why the guidelines ask users not to.
The only claims you've ever made about abuse on HN, unless I'm forgetting something, have been complaints about your ideological opponents. The opposing side makes exactly the same claims about yours. Everyone who thinks this way is sure that HN is secretly dominated by their enemies and the mods are probably in cahoots with them. But they all, of course, have a different picture of which side is dominating—always the one they dislike.
In the case of the OP, it's clear that the submitter is here to promote Citylab. But there's no evidence that the voting on these stories has been manipulated. They're just articles that a certain class of (legit) HN users like and tend to vote for. When we notice a submitter with a promotional history, we penalize the account; we want users to submit stories that they ran across and personally found intellectually interesting, not because they or a friend or an employer have something to promote. Still, this is the mildest class of bad behavior that we see on HN; such submitters usually haven't got a clue that they're doing anything wrong, and they're doing nothing underhanded behind the scenes.