But why people create Coffescript, Typescript, Kotlin (which compiles to JS), and many more? Why are we compiling ES7,ES8,ES9 to compatible version of basic javascript then? Why do we use wasm?

I think this shows the lack of willingness to write a vanilla, all-compatible javascript. Also it seems people use new features without understanding how those get compiled to a lower version.

Sorry when I meant vanilla I did not mean ES9.