I feel like at this point Dart suffers from being a Google project: Google decides its fate, and Google has built a rather poor reputation when it comes to stability. I don't have concrete evidence, but I think the Google culture adheres more to the rolling release and move fast and break things ideology. I personally witnessed several of my own Dart projects needing serious refactoring after just a few years.
Also, I feel like Dart is a maximalist project. "Batteries included" also means a whole myriad of tools and libraries also at the grace of the Google Dart team.
Also, I feel like Dart is a maximalist project. "Batteries included" also means a whole myriad of tools and libraries also at the grace of the Google Dart team.