Not true, but you do get banned if that's all you use the site for, or if you regularly break its guidelines.

https://news.ycombinator.com/newsguidelines.html

HN has a pretty cynical viewpoint on everything. A comment doesn't really feel like a contribution when you're writing it unless you disagree with the parent (like so).

People will find all sorts of reasons to think the article is wrong based on "mid-brow dismissal" or will say any public figure or company is lying about any statement they make.

Plus there's no emojis.

HN moderators discourage humour. Contrast with Slashdot that encouraged it via the moderation system. If everyone has to sound serious all the time, you get a lot of angry sounding posts.