In 2013, it was far from clear that git would win. There was still a sizable amount of users of darcs, Mercurial, svn, and even cvs. Many of the tools of that era would have plugins to support all of them.

I wish we still had that, because git monoculture also means that anything that replaces git first has to reimplement git. This means that just like ASCII or scroll lock buttons, we're stuck with git mostly forever.