If you have any trouble sounding condescending, find a Unix user to show you how it's done.

The line is a sardonic jab at a stereotype from computing culture: that experienced Unix users can be dismissive toward newcomers, especially when correcting mistakes or advocating “the right way” to do things. By framing condescension as a skill that can be taught—and naming Unix users as the putative experts—the quote uses exaggeration to critique gatekeeping and status signaling in technical communities. It also plays on the long-running rivalry between different operating systems and user subcultures, where identity and expertise can become performative. The humor lands because it recognizes a real social dynamic: knowledge can be used either to help others or to elevate oneself.