A lot of folks who have static websites aren't technical and invested thousands of dollars for a WP website. If their site already runs, you wouldn't be providing anything.
A free business idea: write a converter from WP to Jekyll (or Hugo) that converts 95% of a typical WP site right, sell total conversion services, maybe reselling hosting, too.
Here's one I wrote a few years ago to go from Wordpress to Wintersmith.
The Wordpress export format is pretty gross, though.
wget -N --recursive --page-requisites --html-extension --convert-links https://example.com/
I had to turn off HTTPS for the generation time and reportet it as a bug to the developers.
I also converted another WP blog to Markdown and used it with a static site generator. My new site is not online yet, but here is the source of an article aout it: https://github.com/davidak/davidak.de/blob/master/pages/word...