Ballerina is a standalone open source project and does not tie anyone to any WSO2 ecosystem.
Please compare processing JSON in Java vs. Ballerina, typing network data in Java vs. Ballerina, writing HTTP/GraphQL/WebSocket/gRPC etc. services etc. in Java vs. Ballerina, calling network services in Java vs. Ballerina and then you'll see the difference between whatever your favorite Java framework (or rather combination of them) vs. Ballerina.
(I'm the founder & CEO of WSO2 and one of the lead language designers.)
Please compare processing JSON in Java vs. Ballerina, typing network data in Java vs. Ballerina, writing HTTP/GraphQL/WebSocket/gRPC etc. services etc. in Java vs. Ballerina, calling network services in Java vs. Ballerina and then you'll see the difference between whatever your favorite Java framework (or rather combination of them) vs. Ballerina.
(I'm the founder & CEO of WSO2 and one of the lead language designers.)