Git is not "simple" from the point of view of new users. But it is "simple" from the point of view of the programmers of Git. There's the graph structure and some tools to manipulate it. It doesn't do much to hide that.

The underlying code of the application I'm writing would be much "simpler" if I didn't have to add all kinds of features to make it easier for the user.

Also, Git is not so much a VCS application as a framework for version control.