I beg to differ on the concept that github became popular because it integrated social media features. I would assert that github became popular because it offered free online git repo hosting. The social media stuff was only long after the fact, and accelerated under M$ ownership. An old adage was: Every s/w evolves until it becomes an email client The modern version is: Every s/w evolves until it becomes facebook..…
Github's original 2008 tagline was "social code hosting". I'd argue the social nature is what made github, as well as git, popular.