I'm sure there's got to be more to it than this. The intro was too obviously mapable to a relational database using foreign keys and associative tables. Look forward to a post getting deeper into EdgeQL.
Most of the "killer features" are in EdgeQL, SDL, and the tooling surrounding EdgeDB. But the goal of this post is just to describe the graph-relational model of data persistence at a high-level—how graph-relational databases "think" about data. We intentionally defined the term in a way such that it isn't strongly coupled to EdgeDB — EdgeDB is just one possible implementation of the model. And there's a lot more to EdgeDB beyond that fact that it's graph-relational.