How is ReactNatives' JSI approach fundamentally different from NativeScript's type marshalling?

[shudv]

I have been reading extensively about ReactNative's new architecture. A fundamental shift is made possible by JSI which enables native-JS communication. It helps us move away from the old architecture that uses asynchronous bridge. From my understanding, JSI is essentially a type marshalling mechanism from JS to C++ that lets us move data back and forth from native to JS runtime.

Now if you look at NativeScript, which is another framework for cross-platform mobile development, it has been doing something similar since the very start. For example, look at NativeScript's android-runtime architecture - it contains a type marshaller which essentially does what ReactNative's JSI does. If that understanding is correct, isn't NativeScript already at a point where ReactNative is trying to go with the new architecture?

Please understand that the intention here is NOT to start a framework war. My only aim is to understand the fundamental differences/similarities between how these JS frameworks enable JS-native communication. That will allow me to take more informed technical decisions for my project. Thanks!

A related discussion from the NativeScript forum

[shudv]

Another finding - Codegen is documented as another important piece of the new architecture that generates the necessary glue code. Isn't is exactly what NativeScript's binding generator does? Here is the binding generator for android.