Seeing that its open source... its not really trying to sell you anything, now is it? :)

also, the page says one thing.

    Nerves is the open-source platform and infrastructure you need to build, 
    deploy, and securely manage your fleet of IoT devices at speed and scale.

There's two CTA on the site.

- 1) GetStarted - 2) What is Nerves?

Both then proceed to tell you exactly what nerves is and funnel you to code examples, guides, and case studies.