Off the top of my head, other languages that are considering and implementing syntax extensions include Python (e.g. "yield from"), C# (e.g. "async/await"), and Java (lambda expressions).
I actually think that it's pretty low to accuse ECMAScript of "mangling" JS syntax when they are just trying to add modern extensions that make common patterns easier. Of course this function bind syntax is just a proposal and hasn't been accepted into the standard yet. But what about it bothers you so much? What about iterators or shorter function definitions, are those also nightmarish manglings of syntax? I mean, really. The usage of Javascript is evolving from simple embedded scripts to gigantic client/server applications. It's no surprise that the language itself will evolve as well.