Using GraphQL in a microservices architecture can be more efficient and flexible than using traditional RESTful APIs. 

With GraphQL, clients can query multiple microservices with a single request, and can request only the data that they need. 

This can be more efficient than having to make multiple separate requests to different APIs. Additionally, GraphQL allows clients to specify the shape of the data that they want to receive, which can be more flexible than the fixed structure of traditional RESTful APIs.

https://www.moesif.com/blog/technical/graphql/REST-vs-GraphQL-APIs-the-good-the-bad-the-ugly/