Serverless functions are gaining popularity due to their pay-per-execution pricing model, scalability, and ability to give frontend developers superpowers. Devs can build robust backend applications and APIs using simple AWS Lambda functions, making it an attractive option for building CRUD (Create, Read, Update, Delete) APIs. By using FaunaDB as the backing database and Netlify Functions, developers can create a seamless experience between the frontend and backend. The tutorial covers how to set up a CRUD API using Netlify Functions and FaunaDB, including creating functions for each operation, connecting them to the frontend app, and deploying the application. With this knowledge, developers can build scalable and efficient serverless applications with ease.