I spoke to dang about this, last fall, and he was very reasonable and took me off rankban. I think he's trying to do a good job with Hacker News. I have no problem with him, and I realize that moderating a board like this is a hard and often thankless job.
Then, I pointed out a rather obvious pay-for-play story, taking advantage of the Sony hack, about Evan Spiegel in December 2014. (A journalist was, almost certainly because I know how these things work, paid off to say good things about him based on emails that were lacked in the hack. He was trying to protect his reputation, although it's unclear from what.) Since then, I would repeatedly get exactly 5 downvotes to pretty much every comment, all around the same time. Sometimes it would be obvious; it would be a 36-hour-old comment that went from +3 to -2, even though that story had fallen off the front page a day ago. I don't know if this was one person using multiple accounts or different people (Snapchat employees?) I think it's likely that they have some connection to Evan Spiegel himself but I can't prove it.
That said, the Spiegeloids seem to have laid back, because I'm not seeing every single comment get hit with 4-5 downvotes at the same time anymore. (Either that, or they downvote me at different times, making it less obvious.) Maybe they're gone. I can't be sure.
I have still noticed that Hacker News has much more of a willingness to downvote over disagreement. Back in 2010, it had to be a pretty low-quality comment to get downvoted. These days, I see a lot more good comments (and I'm not talking about my own, because I'm a weird special case) that end up light-gray. It's an irksome cultural change and it may be part of why Hacker News doesn't really seem to be growing any more (although it may be that Hacker News doesn't want to grow).