It's amazing how disconnected from reality Susan is... I don't think she even knows it. YouTube is probably the poster child for censorship in the context of genuinely free (1A-protected) speech. I have no idea how this self-stroking "award" can be taken seriously by those who actually monitor freedom of speech (excluding porn, which I don't consider 'speech').
Under a more expansive concept of free speech, where we include things like monopoly market power or illegal use of force as government action; then you could argue that YouTube does censor things due to their large size. It's genuinely difficult to start your own video site and speak without being buried in hosting fees; so I think it's useful to talk about them censoring things in some contexts. However, we've also strayed far away from the First Amendment.
Outside of those concepts; however, I don't think the word "censorship" is very useful. If Hacker News decides to ban me, I can go to many thousands of other private forae in order to speak. Perhaps we should use the term "para-censorship" to refer to these situations in which third parties decide to refuse to do business with you.