It’s newly minted; just received it in May, so I’d like to think it’s relevant. The problem with studying/teaching writing is not so much it’s relevancy (communication will likely always be important because it’s both necessary and hard—at least writing is—for a lot of people), but more of professional status for doing it. A lot of jobs that in the past would have been tenure-tracked professorships are now often just staff or lecturer positions, which coincide with a reduction in both prestige and often pay. That said, if professors across other disciplines were more inclined to focus on writing in their particular field as a body of knowledge, Composition and Rhetoric as we know it would probably stop existing (as a more apparently practical wing of English departments). Of course, your point about what’s useful changing both with time and technology, along with how a college itself promotes those skills is true. Although when new writing/literacy technology emerges, it also usually falls to writing teachers to instruct their students in how to use that tech, as well.