That's because of eslint-plugin-graphql.
It wraps GraphQL source code into a js string tag, we supported this usage by mapping graphql to babel parser at #11.
But @graphql-eslint/eslint-plugin works with a custom estree-compatible parser, then the mapping is incorrect for it.
I'm going to raise a PR to support these two plugins/processors at the same time!
Related to graphql-hive/graphql-eslint#395