None of these cultures handle censorship well. They all originated in an environment where, to some extent, you could say whatever the hell you like.
Many of Reddit's early users came from these cultures, and they were responsible for the early culture of the site.
And now, Reddit is desparately trying to adapt itself, and attract people from Twitter, Facebook, and Tumblr, whose cultures are radically different, and perhaps even to some degree less toxic than the pre-September usenet, whilst also being more toxic. I don't know how.
The point is, a culture that previously only dealt with unacceptability in relative terms - this is unacceptable in this context - is now dealing with absolute unacceptability - this is not acceptable, ever. This isn't a change that people will likely adapt to well. This is prompting a migration to sites like Voat, and others.
The problem is, Reddit is introducing censorship which is incredibly inconsistant to a site where the concept of censorship is anathema - Bans, yes, people get punished for breaking the rules. But having your posts quietly vanish without warning?
No wonder the userbase is pissed.
Unless I got it completely wrong, which is possible.