Big reason why: it's the language behind google's upcoming replacement to Android called 'FuschiaOS' AND Google's new language for building cross-platform native mobile apps (iOS, Android, Fuschia). Dart will see huge growth in 2018 and 2019.
Dart is the language behind Google's upcoming 'FuschiaOS' and 'Flutter' framework for building cross-platform (iOS & Android) mobile apps. Please add dart support! It's not a new language - but with these new applications it's likely to grow fast in 2018 and beyond.