First, thanks to this author for such an excellent treatment of such an important topic. Generally, I would say that being offensive is a form of intimidation, which is a moral wrong.

To that point, another perspective that isn't made explicit in this article is necessity vs. desire. Even if a person thinks a point he or she is making is necessary, the language (or other form of expression) used is always optional. The desire on one person's part to attract attention to the point being made cannot trump using language another person finds offensive. Whether this or that person should or should not be offended by this or that form of expression is not for the initiator to decide. With offense, as with all other forms of possible harm, we have a moral obligation to err on the side of caution.

It would help in this and all other matters of justice if we would lose the notion that liberty is the source or the foundation or the predicate of justice. It is the product of justice. The ethic of justice must be (my studies have taught me) mutual respect (of a basic kind: taking one another into account). A society governed by that ethic would generate the maximum liberty coexisting people can share simultaneously.