> I find it a particularly odd design choice to not make GraphQL spec match the JSON spec.

I can't speak for the original authors, but I can kind of understand it just by virtue of the fact that JSON is quite an ugly format that's hard to write for humans and comes with plenty of opportunity for error (missing quotes in places and the like). Their language also allows the introduction of some higher level semantics like an `Int!` to indicate that an argument can't be null.

Finally, GraphQL's query language has one major feature that makes it worth alone: you can comment things! This is something that you could never hope to do in JSON :/