You have the exact same amount of work regardless of the two, which is reading the documentation. At least with GraphQLi, I can write a query with the docs open and iteratively explore.
If it's graphql then I have to... well, step one I have to learn the query language. And then I have to construct the query to return the data. It's not, like, super hard to go through all of that but it's extra cognitive burden that I don't want to deal with.
I'm currently writing CLI tools in Go and have to use the graphql API for github because it offers data that the REST API does not (I think). I really prefer the REST API wrapper.
... it's literally the exact same thing for GraphQL. I open up GraphQL explorer, look at one root query I'm interested in, and fire off a request. It's really no different a workflow in Postman/Insomniac if I'm working with a GraphQL or REST API.