Deleting a comment because it is insulting a person is moderation. Deleting a comment because you don't like it, it doesn't conform to your views or you find it outrageous, silly, inflammatory, false, fake is censorship.
Your comment brings this out because some subset of "outrageous, silly, inflammatory, false, fake" is right on the cusp, and making those calls (to moderate or not to moderate?) puts tremendous pressure on one's own feelings and beliefs. What helps one do it neutrally is self-awareness, but that is the scarcest thing there is. It takes a decade of hard work to distill a bit more. (Edit: and I'm not claiming to have much; just that it's needed.)
I'm uncomfortable with the "false" / "fake" end of your spectrum because we don't have a truth meter. Who am I to decide what's true or false or "mis" or "dis" for anybody else? I'm not taking on that karma.
"Inflammatory" is easier to work with because it's about predictable community effects and one can moderate for community cohesion. Moderating that way ends up excluding truths that the community can't withstand, but such truths probably exist for any community. Groups may even be defined by what they exclude. We can try to stretch those limits but there's only so much elasticity available.
I blanched when I read "Moderation is the normal business activity of ensuring that your customers like using your product" in the OP, but actually that's basically saying moderation is about community cohesion and I can't disagree. But the secret agenda, on HN at least, is to stretch it.
Well, in very small doses numbers help. It is easier for a small group to watch the blind spots of each member. As the numbers scale up to serious group sizes things seem to fall apart again as a hive-mind forms.
Which means that the sensible thing to do is to form a committee of intelligent people with good incentives, then go trustingly with what they suggest. Which is, coincidentally, a successful model that governments use. All the politics is generally a distraction from the real work being done by committees.
At the same time the hive mind is quite often a protective defense against insurgency in forms.
This seems to be a problem with the comments in this entire post. We're taking community as individuals doing individual things, and in small forums this is commonly true. But, when the group grows larger and money is on the line that assumption should be discarded. In astro-turfing for example, a seemingly large group of 'users' will direct communication on your forms via somewhat 'rational' communication, but possibly disliked by a lot of members. Then you'll notice a group that seemingly counters the astroturf to the level of absurdity that turns more 'hearts and minds' towards the astroturfers (guess what, the counter turfers were also the astroturfers).
You typically end up with one of two situations. The forum either takes on the ideas of the astroturf group and it becomes encoded in their ideals, or the fend it off, but in doing so embrace some of the extremism implanted by the astroturfing group in the first place.
Also, what happens to any group when 4chan decides to raid you for the lulz?