Not necessarily, on small projects that are being rapidly developed it's very common that you need to change many times the data structures returned by api, as front-end is iterating on the design and ideas and figures out the new pieces of data that they need. Mapping the results of DB queries into complex structures & entities, and juggling it to fit the latest needs of front-end/app devs used to take a big chunk of my back-end dev time (and nerves). GraphQL can extremely simplify and speed up these iterations.