Faster WebAssembly isn't listed on the roadmap, so you are disappointed, right?
Wasm is currently considered "around half as fast as native"[0]. The Wasm design, Emscripten compiler, and browser compilers all have a part of responsibility in this, but I suspect that browser compilers have the largest share. Mozilla created The WebAssembly Explorer[1] which shows good-looking ".wat", but bloated "Firefox x86 Assembly" compared to "LLVM x86 Assembly". I hope they intend to use this tool to improve Firefox x86 Assembly.
Wasm is currently considered "around half as fast as native"[0]. The Wasm design, Emscripten compiler, and browser compilers all have a part of responsibility in this, but I suspect that browser compilers have the largest share. Mozilla created The WebAssembly Explorer[1] which shows good-looking ".wat", but bloated "Firefox x86 Assembly" compared to "LLVM x86 Assembly". I hope they intend to use this tool to improve Firefox x86 Assembly.
[0] https://github.com/WebAssembly/binaryen/issues/1070
[1] https://hacks.mozilla.org/2017/03/previewing-the-webassembly...