[sbegaudeau]

I use GraphQL as my main solution to build APIs these days and I have worked with GraphQL for almost 4 years.

I agree with you that "being able to project out individual fields seems like a niche benefit" and I almost never use it to let anyone ask for anything. I rely on GraphQL mostly for its schema in order to have a coherent view of my API at all time. I can thus easily validate my frontend queries during continuous integration and I know the structure and type of the result that I will obtain from my queries.

When I refactor my API, I can evaluate the impact quite easily since my build will tell me about invalid queries in my frontend and unused fields too (since I am building my API for known clients, unused stuff has no place in my API). It brings me the same security net during changes to my API as TypeScript does.

Since I'm not building my API for unknown clients which could ask for anything but instead for specific clients that I can control, I am still doing most of my joins in my datastore. I am relying on a Java implementation of GraphQL and I don't feel any GraphQL-specific complexity on the backend, it may be different with other implementations of GraphQL. In Java, with a minimal amount of annotations, most of my schema is created automatically from my data classes.