I personally don't think of Jamstack sites/applications as being 100% static. The core nature of the Jamstack is the ability to extend functionality with APIs/microservices (jamstack.org have a diagram example: https://d33wubrfki0l68.cloudfront.net/b7d16f7f3654fb85723603...)

Having separate systems is (at least in my understanding and experience) a core design feature of the Jamstack.

Your question is valid. Why not go all the way to a CMS? If the author wants dynamic features AND doesn't want to build them himself, he might want to reconsider Wordpress.

> Why not go all the way to a CMS?

Because that's not considered cool anymore and doesn't give you the opportunity to play with lots of different tools for no reason other than over-engineering.

The other comment mentions a technically valid point about separation of concerns and delegating maintenance to separate teams (essentially the same value proposition as microservices), but in the real world, is this an actual problem for 90% of websites out there, especially when talking about simple, personal or small-business websites? I don't think so.

I would say that what most people commenting on this thread don't realize are the benefits of storing static content as code in plain text files.

Text content in a database is unversioned and only accessible through SQL queries in sophisticated dedicated clients; while content in markdown files can be changed with plain text editors and treated just like source code, getting all the advantages of branching, diffing and merging versions among multiple users.

Think about whether you'd like to work with all your source code stored inside a CMS like Wordpress instead of VCS like Git, and you'll begin to understand why Static Website Generators are a good thing for the people responsible of updating the content.

Is anyone working on a Git-based CMS that can be accessed through REST APIs or through Git?

It's called GitHub pages.

And several third-party developers are building user-friendly CMSs on top of it.