The big problem with CSV is that it has no convention for Graphs. CSV Relationships in Neo4j are custom made. CSV was not made for that. You would need to create a standardized convention for everyone to follow. But how to make all CSV users standardize as we need?
We would also need to maintain a convention for Exports. Which would not be compatible with any other tool that uses CSV. Our JSON export isn’t compatible with any tool out there, but JSON is easy to sanitize .
Easier is to convert CSV to JSON or something. You can use openrefine https://openrefine.org/ - it’s a very good tool and has a Dgraph compatible export. You just need to sanitize the data well. Using OpenRefine itself.