I actually think that considering the website to be a public space, same as a street corner or park, is a strong stance to take. It ensures that only the government can come in to suppress speech, and makes it easy for people to understand what can and can't be shown. The internet has been missing this kind of thinking, which connects the online to the offline in a clear way.
P.S. to the weirdos attacking the commenter over this, I'm really not clear what your argument is. Sorry :(
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