Hacker News is link aggregation site with links to and discussions around technology related subjects. It is run by the "Y Combinator" investment fund. Users can post links to stories, comment on links to stories and vote stories and comments up or down.
Shadow Banning Practice
Hacker News uses shadow banning as a standard tool. They shadowban based on either usernames or domain names or both. I became aware of this because someone pointed out to me that my account there is shadowbanned. I verified that this is indeed the case by using two web browser profiles, one where I was logged in and one where I was not. Several random people suggested that the reason for the ban is likely that this site has some South Korean pop idols in some of the screenshots:
"dang hates cute girls"
I do not know who/what "dang" is or if that person actually hates cute girls.
The reason for the shadowban could, alternatively, be that I simply don't use or care about Hacker News. It was simply yet another place to dump links to articles on this website. They may have (somewhat rightfully) deemed that to spam.
The AGPL licensed free software web content management package Lemmy, or the more liberal Lenny fork of that package, can be used to quickly setup a website that looks and behaves very similarly to the way Hacker News does. A dozen or so website use it. None of them are focused on the technology niece Hacker News is focused on as of mid-2020. Someone is bound to setup something similar sooner or later. You could do that yourself.