Comment by jandem

Crypto miners written in JS existed long before WebAssembly. Back then people also compiled large C++ code bases to (highly obfuscated) JS code and out of these heroic efforts grew asm.js which then evolved to WebAssembly. WebAssembly is a much better compile target than JS with more low-level types and primitives, but it's very similar to JS code in what it can and can't do in the browser.

Compiling a C++ application to megabytes of JS code doesn't make the result any more open-source or non-DRM than compiling the same thing to WebAssembly (you could translate Wasm to the equivalent but slower JS code).