It would be very difficult to overstate how strongly I disagree with your statement. HN mods have shown a strong tendency to shut down discussions that turn into flame-fests. The most common topic for such discussions is politics. But they will post on political discussions, begging people to keep it civil so that they (the mods) don't have to shut the discussion down.
If you think that HN mods are taking a political side, well, I have to say that I don't see it. I see them trying to behave as authoritarians only to the degree that they need to to keep the conversation from crawling into the gutter. (And I see them not always doing that perfectly, but it seems to me that the intention is not to take sides.)
And I would say, then, that the problem is more likely that the anti-authoritarian political crowd posts flames, or else that they attract flames in response. If you can't state your anti-authoritarian view without pouring gasoline on the conversation, it's going to look (to you) like the moderators are pro-authoritarian. But if every time you state something anti-authoritarian, your opponents consistently light the conversation on fire, it may have the same effect.
Bottom line: I don't think the problem is the mods. The problem may be you. I'd encourage you to seriously consider that possibility, rather than just dismissing it. Or it may be that there are enough trolls and flamers on the other side that we just can't have a conversation without it destroying the forum.