Not to assume, but that sounds like a comment from someone who only uses GitHub for interacting with git. I agree that GitHub helped spread the popularity of git, but I hesitate to say with absolution that it's the only thing that makes git popular.
Anecdotally...
When I first began my git adventures, nearly 10 years ago, I was extremely apprehensive. I knew SVN. I liked SVN. I had no reason to go elsewhere. And then I tried git (albeit using a GUI at the time), and it didn't click. So I went back to SVN. Later, after being forced to use git for a project at work, I started to understand what makes it special. I finally felt I had a version control system/tool that I could trust without being so hands-on like I was with SVN. Put simply -- git _just_ works. The concepts take time to really grasp (rebase versus merge, reflog, etc), but once grasped, it becomes very easy to see why it is so popular.
I now use git locally as much as I use it with a hosted repository (GitHub, GitLab, BitBucket, etc). I use both command line and GUIs, and I thoroughly enjoy being able to trust git so completely.
Anecdotally...
When I first began my git adventures, nearly 10 years ago, I was extremely apprehensive. I knew SVN. I liked SVN. I had no reason to go elsewhere. And then I tried git (albeit using a GUI at the time), and it didn't click. So I went back to SVN. Later, after being forced to use git for a project at work, I started to understand what makes it special. I finally felt I had a version control system/tool that I could trust without being so hands-on like I was with SVN. Put simply -- git _just_ works. The concepts take time to really grasp (rebase versus merge, reflog, etc), but once grasped, it becomes very easy to see why it is so popular.
I now use git locally as much as I use it with a hosted repository (GitHub, GitLab, BitBucket, etc). I use both command line and GUIs, and I thoroughly enjoy being able to trust git so completely.