As JavaScript is transitioning from the dark ages as a language of ridicule to a respected language of it’s own, it is obvious that some of the rough edges need polishing.
There is no rougher edge than the global namespace issue and the difficulty providing encapsulation. Even for a seemingly trivial JavaScript application, it is no longer OK to just whip up some JavaScript files and assume that you can maintain the code base as it grows. The application now lives in the browser and the amount of code you need to maintain requires modularization.