Or it shows that they see that there's already an established base of people using TypeScript, more than Dart, and choosing to follow where the community exists

Or it shows that they see that there's already an established base of people using TypeScript, more than Dart, and choosing to follow where the community exists. Throughout the development of Angular 2 the team also talked with the developers of other frameworks, libraries and tools, which shows that they believe in the community more than trying to push their own agenda.