If you believe, as progressives do, that human nature is not fixed, and hence is not a basis for understanding natural rights. And if you believe, as progressives do, that human beings are soft wax who receive their shape from the society that government shapes. And if you believe, as progressives do, that people receive their rights from the shaping government. And if you believe, as progressives do, that people are the sum of the social promptings they experience. Then it will seem sensible for government, including a university’s administration, to guarantee not freedom of speech but freedom from speech. From, that is, speech that might prompt its hearers to develop ideas inimical to progress, and that might violate the universal entitlement to perpetual serenity.
"Human nature is not fixed, and hence is not a basis for understanding natural rights." While there obviously is a "human nature" of a biological sort or else we couldn't separate human beings from other species, what Will means to claim is that progressives deny that unchanging moral or ethic claims follow from human nature. Will's own position, presumably, is that we can deduce from an understanding of our nature as humans a "naturally right" social order, or that nature (or "nature's god") confers an inalienable sovereignty on each individual that entitles individuals to resist encroachment upon it. Since God has proven a poor guarantor of human rights, presuming that you attribute them to him, Will must mean that man is the guarantor of his own rights as a matter of instinct, the rights being natural, even though his intellectual tradition argues that the true natural rights are discovered through reason rather than instinct.
"Human beings are soft wax who receive their shape from the society that government shapes." You may be a progressive if you believe this, but I don't know if anyone believes that government exclusively shapes both society and individuals, as Will implies. I am not aware that progressives reject the idea of "civil society," that there are institutions independent of the state (but not of laws) that are crucial in defining each person's identity. As for the rest of this claim, unless all of Will's erudition and ideology are innate, then he has been shaped from outside, though this doesn't mean that there can't be resistance to the shaping from inside, or a complementary self-development as people learn to reason.
"People receive their rights from the shaping government." Practically speaking, rights require a guarantor, and given likely disagreements over assumed natural rights the only effective conferral of rights comes from the only effective guarantor, the government. Governments must determine what rights are in society rather than in any state of nature to which individualists or ideologues might appeal.
"People are the sum of the promptings they experience." Again, I doubt whether any self-styled progressive believes such a thing. They more likely believe that the human mind is capable of analytical and even creative reason, but they're also likely to believe that these are inescapably responses to experience rather than phenomena generated in a "natural" vacuum.
Yet even if I agreed that the ideas listed by Will were progressive beliefs, or if someone actually chooses to affirm them all, I don't see how this leads to Will's conclusion that progressives would want government to guarantee "freedom from speech." Will has made a strawman of the premise that progressives deny intellectual autonomy. His "progressives" are tantamount to totalitarians, and maybe there is a certain trivial totalitarianism on college campuses today. But as I must wrap quickly this evening I'll conclude that on the subject of progressivism, much less progress, George Will is full of crap.