Nope. Totally different. In your example, the poster on HackerNews would only get down-voted and thus, censored. Okay. No big deal.
What's happening at the universities right now is different. It is not censership. At these, universities, a person who says, "Edward Snowden is a traitor" would get fired, because students would force the administrators to fired the person they disagree with, because it's "offensive" to call Edward Snowden a traitor.
So totally different. On HackerNews, it's just a down-vote, a simple censorship. At the universities, the person loses his job/education/livelihood, all because he has a different opinion about Edward Snowden. That's not censorship. That's "ruinning-people's-lives-for-having-a-different-opinion" but trying to pass it off as just a simple censorship.
If someone says something unpopular on hackernews, ie "Edward Snowden is a traitor" they will be downvoted into oblivion. You could say that hackernewws censored the person's ideas, but I think the reality is that what they said wasn't very popular with the people they said it to. I think this effect is just as relevant and predictable with online communities as it is with college campuses.