So where are the masses of serious C#/ Java/ <pick-your-language> developers using transpilers to write the logic of their web applications? I think it is catc

So where are the masses of serious C#/ Java/ <pick-your-language> developers using transpilers to write the logic of their web applications? I think it is catching on with C++ game developers, who want to be able to run the same codebase natively or in the web browser. The Unity 3D game engine has built-in support for this using WebGL, for example. I don't know if CLR or JVM languages have been successfully transpiled to the browser using asm.js / WebAssembly (it wouldn't be very efficient at all, so I doubt that will ever be popular).