Steemit is an open blockchain so everything is open for all to see. Your posts, comments and even you wallet.

You can be censored by all-powerful central authorities on Youtube and Twitter but this cannot happen on Steemit. However the crowd can downvote you to oblivion.

If your reputation sinks below a certain level your posts and comments are automatically hidden. This effect might lead to social cooling but this might be an appropriate type of censorship?

I find people on Steemit tend to be more polite because nasty behaviour can cause you to make less money. This is a good thing and leads to a healthier environment.

In contrast, sometimes things on Reddit can get pretty nasty.