You're getting a lot of pushback but I agree with the sentiment of fully owned. Sure, the git repo and static files are hosted elsewhere for now. But you can easily switch that place any time. Meanwhile all the important stuff: the post data, the code to format them, the domain name, the process itself. That's all in your complete ownership and control. It's a very different bargain than, say, hosting things at wordpress dot com.
But the git repo is also fully on their local computer. Isn't that owning? Just because there's a copy elsewhere does not invalidate the local copy!