Git is definitely a tool of the sort that you need to learn before you can use it well. Once you do, it's not really nightmarish at all, it's quite convenient.
I would never argue that it is user friendly though.
But for non-programmers, I would say that user-friendliness is very nearly everything. They are never going to keep the "simple" underlying model of an directed acyclic graph in their heads to let them intuit how to work with it. For them, they need an interface that baby steps them through the process and makes it obvious what to do at every turn.
I would never argue that it is user friendly though.