If I understand you correctly, you're wondering why wasm is controlled by the front-end Javascript (UI).
I'm not an expert in how wasm is implemented, but from what I've seen and read, the flow of control can go both ways: Javascript can make calls to the wasm component and have code executed (and return a result).
But it's also possible for wasm code to manipulate the web page directly. I've seen a demo of (a slimmed down version of) .NET running in a browser, running a complete Todo app, all written in C#. No Javascript needed.
If I understand you correctly, you're wondering why wasm is controlled by the front-end Javascript (UI).
I'm not an expert in how wasm is implemented, but from what I've seen and read, the flow of control can go both ways: Javascript can make calls to the wasm component and have code executed (and return a result).
But it's also possible for wasm code to manipulate the web page directly. I've seen a demo of (a slimmed down version of) .NET running in a browser, running a complete Todo app, all written in C#. No Javascript needed.
@supermanitu , why do you say "this is not a good thing" for JS to be used for more than just UI ?
Javascript is a full fledge programming language as capable as others. Why couldn't it build an app ?