My boss gave me a single page website to develop, and Jekyll is mandatory. of course I dont directly question my hierarchy. I'm not really used to jekyll so perhaps there is something I didn't get. How would you justify its use for a single page website ? (and not a single page app)
Jekyll does not necessarily operate on the webpage level. With Data Files, you can have data in multiple files that can be rendered on the same webpage.
If it’s useful in this specific case would depend on the site, your workflow, and especially what you’d use instead of Jekyll.