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.