"Optimal" is very broad. Optimal in one aspect might not be optimal in another aspect.
For instance, Ember and Angular in my opinion is optimal in terms of convention. Follow convention, and you can write apps in less time. Break convention, and you aren't "optimal".
React with Flux is optimal in terms of predictability of an app's behavior. One can simply eyeball the data and code and say "oh, this should happen if this is put in". Break this architecture, and you're in for unpredictable apps.
jQuery is optimal in terms of cross-browser utility APIs. However, if you find yourself falling back to vanilla, then your code is not "optimal" in terms of cross-browser compatibility.
Execution isn't the only aspect people care about. It's what they call "abstraction" and abstraction has its tradeoffs. Otherwise, we'd all be writing vanilla JS and sacrificing what matters most - getting things done.
For instance, Ember and Angular in my opinion is optimal in terms of convention. Follow convention, and you can write apps in less time. Break convention, and you aren't "optimal".
React with Flux is optimal in terms of predictability of an app's behavior. One can simply eyeball the data and code and say "oh, this should happen if this is put in". Break this architecture, and you're in for unpredictable apps.
jQuery is optimal in terms of cross-browser utility APIs. However, if you find yourself falling back to vanilla, then your code is not "optimal" in terms of cross-browser compatibility.
Execution isn't the only aspect people care about. It's what they call "abstraction" and abstraction has its tradeoffs. Otherwise, we'd all be writing vanilla JS and sacrificing what matters most - getting things done.