I've long been skeptical of this line of thinking emanating from major thick client JS framework authors. I think they underestimate what people are capable of.
> Over time, Ember will become like gcc -O3 for web apps, intelligently optimizing them and delivering them as fast as possible, piece by piece, to your user’s browser.
I've been observing these trends for years and what I'm seeing is this: ever since these new thick client JS frameworks became so trendy, web performance has dramatically decreased, not increased.
This one-two combo punch of framework authors condescending their users as "our target audience is devs who can't hand code" while simultaneously promising performance that's just as good as hand coding and perpetually failing to deliver is a toxic stew that is crippling web performance.