But that's already possible today without WASM. E.g. there are react plugins that render to canvas, as being used here together with some WebGL: http://www.anagram.paris/ (try to drag). And yet, we don't see this often being used. Instead, we see more DOM being used on new places (e.g. electron applications). I think if WASM+Canvas would be the way forward, we'd have already seen it by now, since it was already possible in plain JS or with asmjs if you really hate JS that much.
In the end, HTML & CSS is fast enough for most business-style applications and frameworks like angular/vue/react are pretty good ways to make frontends.
In the end, HTML & CSS is fast enough for most business-style applications and frameworks like angular/vue/react are pretty good ways to make frontends.