[mdhb]

I think you are missing the fact that Dart is actually an incredibly nice language to work with in a way that Go absolutely is not.

[api]

The problem is that it’s yet another language. It’s the cognitive load and the inability to easily reuse code across a project.

[Capricorn2481]

That seems more like an argument against Go. Dart is the language more familiar to the average dev, and you're gonna have an easier time translating that to Java/C# than you are Go.