Perhaps the best I can come up with is the debate around good encryption, network communication, and the government's abuse of people's rights; but in this example, the counter-arguments I've heard have just not been convincing, which I find different from not getting fair treatment.
For instance, I pretty much accept that pro-Brexit posts will always get downvoted, even posts that state a matter of fact with citations. I don't care, I have great karma scores already and I've noticed that initial negative scores tend to end up slightly positive -> the problem eventually gets corrected, but it's incredibly obvious that lots of people simply downvote posts they disagree with regardless of content.
Basically anything to do with the cult of diversity. The double standards and refusal to acknowledge charlatans is impenetrable. It's no problem to demonize approved groups of people based on hearsay, but considered harassment to point out fraud or lies from protected demographics.
That's a holy cow that HN has slowly but surely adopted. The response is usually a kafkatrap: accuse the poster of being dishonest, and treat refusal as an admission of guilt.
If no explicit statement can be picked at, you get accused of "dog whistling".