> What Is the Definition of Censorship?
This should be answered by a dictionary or an organisation with specific knowledge of its history. Perhaps consult Wikipedia¹ and the ACLU².
> Take HN for example. I would have thought hackers
HN is not a uniform blob of people. Neither are “hackers”. Nor is the former frequented only by the latter.
> would be free-speech oriented
As XKCD reminds us³, “free speech” does not mean people have an obligation to listen to you. If you go into a building and begin spouting insults at everyone inside, it’s not censorship if people ask you to shut up and leave.
> in a group, they are just as good at punishing differences as high-school bullies.
You seem to have a point you want to make. If that’s the case, please make it directly and honestly. Indirect jabs⁴ are more likely to get you downvoted than the content of your ideas. HN optimises for curious, kind conversation. Snakiness is explicitly frowned upon⁵.
¹ https://en.wikipedia.org/wiki/Censorship
² https://www.aclu.org/other/what-censorship
³ https://xkcd.com/1357/
⁴ https://news.ycombinator.com/item?id=36197063
⁵ https://news.ycombinator.com/newsguidelines.html