The [Route] on the Request DTO is a custom route you define that you want your Services available from, it’s unrelated to the pre-defined Routes that’s automatically available in ServiceStack to call your Services.
All of ServiceStack Service clients except for the C#/.NET Service Clients use the pre-defined routes to call your Services when sending Typed Request DTOs.
If you want to call your custom route instead you will need to specify the path and Typed Response DTO, e.g:
const client = new JsonServiceClient("/");
const response = await client.get<HelloResponse>(`/hello/${name}`);