The proposals suggesting markdown + git just sound like tone deaf proposals from 'coders' that are trying to push their square peg through a round hole. More appropriate proposals would be LaTeX + git or Word + subversion or some other vcs that has good binary support
Nonetheless, agree with the author that I don't see anything disturbing Word in that space for a long time, as good luck trying to get a middle-aged with minimal tech understanding to learn and use LaTeX over Word.