HN is self moderating (or rather community moderated). If people don't like certain posts they won't vote for them. If HN starts banning websites because some people don't like them then it takes the power away from the community and then you are on a slippery slope of moderated content and a world of approval conflicts and power struggles.
You or I might not agree with every post on HN but we have the power to not vote, or if you've contributed enough to downvote.
Of course there are always exceptions. Spam and illegal content are examples of this. But then we have the ability to flag those posts.
A moderated HN is one I would not use.