There is a json (technically object) to graphql converter up on npm I use to dynamically create queries. I use it sparingly due to verbosity https://github.com/kadirahq/graphqlify
valid point, but are you talking about the schema or the results. For Schema, it makes sense to have a different DSL as JSON's cons include the inability to describe types on values.
Just with 3 types (string, number, boolean), we can not cover more advanced types.