There are some that have been setup like that. If I wasn’t going to use the @auth and was going to build my own GraphQL server, I would use the DQL endpoints instead of the GraphQL endpoint.
There are quite a few better examples now of using Auth0 with the GraphQL endpoint for a complete setup. The @lambda directive can now also handle a lot of business cases.
It might be easier, but you would have to handle then server side caching, remedy the N+1 problem, and make sure you handle the over and under fetching problems. And this doesn’t even begin to start the problems of generating inputs and creating relationships by reference. A SQL database doesn’t make sense behind GraphQL because it is requesting structured data into a flattened table and then parsing that flattened table back out to fit the schema.