WebAssembly is not much faster than JS, harder to develop and debug, and requires even more extra tooling.
It’s a useful technology but it’s never going to be the primary choice for application development on the web - merely a tool in the toolbox.
So expect the comeback of Flash, Silverlight, Applets, ActiveX, ....
What to do a Flash like game without anything related to JavaScript?
Pure C, C++, Rust with SDL, Unreal, Unity, ....
Miss Silverlight? Check Blazor with Ooui bindigs for Xamarin.Forms.
Go devs already have their design document for WebAssembly runtime ("WebAssembly architecture for Go").
Qt already has a prototype for WebAssembly, with improvements planned on 2018's roadmap.
And many other projects are ongoing.
The pandora box is open, the only back is if the browser vendors stop developing WebAssembly.
WebAssembly is not much faster than JS, harder to develop and debug, and requires even more extra tooling.
It’s a useful technology but it’s never going to be the primary choice for application development on the web - merely a tool in the toolbox.