But the client already had to consider what data it needed.
The only difference is that in a REST world it needed to make several calls to fetch all the data (often waiting for resource references in the nth response before being able to build the (n+1)th query) whereas now it can fetch them all in a single query.
So if anything it reduces the client complexity, as well as making it much easier to extend the API to support new client requirements without having to resort to REST-style versioning.
The only difference is that in a REST world it needed to make several calls to fetch all the data (often waiting for resource references in the nth response before being able to build the (n+1)th query) whereas now it can fetch them all in a single query.
So if anything it reduces the client complexity, as well as making it much easier to extend the API to support new client requirements without having to resort to REST-style versioning.