For me, it's become too clunky for a basic blog, and the fact that it stores your content in a database makes managing it a pain. It ties me to Wordpress and only Wordpress - anything I want to do requires logging in and navigating the admin interface, which I'm not a fan of.

By comparison, flat-file CMS's allow me to edit, search and process my content using whatever tool I like. I can update my blog directly in the terminal, or in Github from work and have the changes pushed out automatically by CI. They're not making hundreds of database calls every time I want a page, so they're blazing fast. I can have simple scripts output to a text file and have it rendered as a status page. And if I want to migrate to another solution, my content is literally a bunch of text files that I can just copy to whatever shiny new thing just caught my eye.