Reading the article, the sysadmin is described as the person who constructs and maintains the environment the code runs in, including the physical machines, but also things like dependency management (I infer).
Given that just about everything except the physical machine can be handled through devops automation (from experience), and those things don't require "special" skills other than docker/ansible knowledge, why are sysadmins still considered separate from software devs?
On a more opinionated note, I think that using people, and not code to setup the operating environment of their application is pretty inefficient nowadays.