Maybe it's most accurate to say that Javascript is the x86 of the web. Modern CPU's have a totally different internal semantics but emulate the x86 machine model externally. Seems pretty parallel to how asm.js works.
The analogy was getting at the fact that in asm.js, JavaScript is used almost as a byte code input to a compiler that has a very different underlying machine model, just as x86 is used as such by modern x86 CPUs. In both cases the somewhat strange dynamic has arisen from the pervasiveness of devices that understand x86, JavaScript. Whether JavaScript or x86 is more prevalent is really neither here nor there.
