I suspect that is never going to happen, for two reasons:

1) verbosity, on its own, does not make a difference on the web - HTML and Javascript are both generally super verbose, and haven't had any accepted "simple binary encoding" designed for them in those 20 years. What does get implemented is minifiers and compressors (gzip encoding or otherwise), both of which will provide benefits to asm.js comparable to what a bytecode would, and would not require any buy-in from browser maker (the same attribute that has made asm.js successful and PNaCL unsuccessful so far).

2) Historically, anything that is not backwards compatible and does not degrade gracefully is NOT easily adopted by Browser makers, or by websites, unless it provides something that cannot be achieved without it (e.g. WebGL gets some adoption because there is no alternative; but ES6 will get little to non in the next 3 years except as a source language translated to ES5)