I don't understand this argument at all. You don't have to be on the bleeding edge. In fact I recommend against it for nearly all cases. If you want to write standard ES5, and skip all this stuff, you can! There is no one holding a gun to your head telling you to keep up "or else".
I pick and choose the tools I need. Some are new, some are old. This goes for any language I use, too, not just JavaScript.
I'm still using browserify, knockout and lodash for all my projects, been using knockout for over a year and it has been rock solid, had zero issues that where traced back to knockout, browserify has worked very well for me same with lodash.
I keep an eye on what is coming down the pipe but I don't buy into anything until it's been around long enough for me to get a good grasp on what the lay of the land is.
In the meantime I have a working stack that allows me to accomplish anything I reasonably need to and I know it'll work.
For those not au fait with Knockout, recent releases add HTML components, deferred and pure computeds and in 3.4 they increased performance through hot paths over 100% making it insanely faster.
I like it a great deal.
Actually the language also needs a total freeze in features. ES5, ES6, transpilers, this and that and bla bla. I used to love language geekery, not so much after a few years of JS exposure. And now there is WebAssembly which is supposed to be a "game changer". Fuck that. I don't want the game to change anymore, I just wanna play.
Or perhaps, I'm just getting old.