spankalee responded to you already[1], how much more clear can people be?
To the much more important point, the development of important features stalled for AngularJS as the team was busy working on Dart version. This is the main problem.
Not true. Google grew the team. Take a look at the activity on Github. The velocity has been consistently high throughout the development of the Dart fork: https://github.com/angular/angular.js/pulse
If there was some important feature you wanted, you are always able to submit a PR yourself. That's how open source works.