The value prop of Sphinx goes down a lot if you're not using reST because you can't use the extensive catalog of directives, such as the ref directive that I mentioned in my first comment. If you must use Markdown then there's not much difference between Sphinx and all the other Markdown-powered SSGs out there. In other words there's not a compelling reason to use Sphinx if you've got to use Markdown.

From Sphinx's Getting Started page:

> Much of Sphinx’s power comes from the richness of its default plain-text markup format, reStructuredText, along with its significant extensibility capabilities.

https://www.sphinx-doc.org/en/master/usage/quickstart.html#g...