One other that helps JSON/REST to remain defacto these days, is not just a web browser support. But also nice mobile clients like Retrofit. Retrofit seamlessly

One other that helps JSON/REST to remain defacto these days, is not just a web browser support. But also nice mobile clients like Retrofit. Retrofit seamlessly converts JSON data by means of json de-serializer, into Java classes. So we get typefull semantic (but, albeit at run time only). I have retrofit integrated with RxJava, and when I looked what it would take to 'plugin' gRPC, I found that I have to change not just my backend, but all the wiring for the mobile frontends. And, at the time it looked like too much work. If Retrofit, would make it transparent JSON vs gRPC -- then it would be great for folks that already invested into Retrofit/JSON.