With enough luck and given time you will be able to skip JS at all! If the community will find the life force after wasting many years on SPA, then we might even see some HTML—near-free canvas/WebGL GUIs!
All this will have to be redone in canvas for no good reason and I doubt it will be nearly as good as what browsers can do already, and we will lose a lot of openness and interop.
Expect the revenge of browser plugins.
https://github.com/appcypher/awesome-wasm-langs
https://github.com/mbasso/awesome-wasm
As for Microsoft, they just announced the Blazor project.
https://blogs.msdn.microsoft.com/webdev/2018/02/06/blazor-ex...
Thank browser developers for opening the pandora box.