Free speech has nothing to do with the speaker. It is entirely about the audience. Does the audience have a right to hear what fellow occupants of its environment think? Students presumably attend university precisely to learn what people they have not heard before have to say. Students are paying for the privilege of hearing views they disagree with, because hearing those views may change their minds or sharpen their resolve, both of which are benefits.

Yes, there is an Overton window, but only because some issues really are settled. The earth is round and the Holocaust happened. Not enough audience members will get any marginal benefit from hearing contrary views to justify the resources devoted to their being given a platform. But even ridiculous views should not be censored, because knowing that there are idiots around us is useful, and only by letting idiots rant do we learn of the dangers they pose.

Hurtful falsehoods are punished (but rarely censored) in the US, because the audience gains nothing from them and the individual victims suffer private damage from the misinformation. Group defamation is a problem, but there is no way to identify its edges, and, more important, the audience needs to know that people hold such views. I don't get much benefit from hearing John claim, falsely, that Jane is a thief. But I do benefit greatly from learning that the Proud Boys are saying that Jews are out to "replace us," even if their claim is wrong, and even if they know it's wrong (although I doubt many of them do know that). Because I need to know the extent to which my group is hated, slandering my group must be legal.

We give speakers the "right" to speak simply as a mechanical matter. The censored speaker may be the only one who knows - or has reason to care - that his audience is being deprived of his particular wisdom. So we say the speaker has the right to free speech. But the right is wholly derivative from the benefit to the audience of knowing what others believe. With the audience's access to information as the polestar, free speech issues become quite straightforward.