I don’t think so. With only freedom of speech, the government could still ban access to all foreign-country-hosted read-only sites – sites without commenting or other interactivity. That would include many informational sites and blogs.

And does this prevent that? China and Iran signed on as well.

In practice, no, because UN resolutions are only as good as their ability to enforce them, which in the case of general-assembly resolutions basically boils down to no ability, except attempting to shame people who flaunt them. Only a handful of UN organs (e.g. the Security Council and the International Criminal Court) have anything approaching teeth.

One of the problems of "freedom of speech" is that many people have bundled a lot of concepts into "speech". There are a great many Internet activities that would be difficult to capture as speech.

Reading a political screed, for instance, is not speech. It is probably protected in some other way, but I'm actually unaware of how. (Actually, considering workplace laws, I begin to suspect it's not protected.) Differently, is clicking a Like button considered speech? What about Unliking? How about transferring a file, or maintaining a personal wiki that no one else has access to?

These aren't questions I want answered anytime soon. I'd rather leave them alone and simply say that people should have the opportunity to engage in these activities, full stop, without having to figure out whether or not they're speech.