Status of streaming with the binary wire format

The readme section for `mode=grpcweb` notes that "Only unary calls are supported for now". This line [dates back to 2018](https://github.com/grpc/grpc-web/pull/251). Is this still correct? Are there any plans to resolve this wire format incompatibility?