> People who talk about auto-generating GraphQL wrappers for Postgres database schemas (not the author of this post, to be clear, but it's common enough) are missing the point entirely. The whole point of GraphQL is to span heterogeneous and independent data sources;

I don't think they are missing a point; rather, they have a completely different point: eschew a backend and use GraphQL on a DB + a frontend that gets all that data. If you're developing rapidly and don't have complex backend logic, I can see why you'd want to do that.