But I think keeping in sync changes in API, hardware device drivers and new interactions across different platforms and device will still be nightmare and in general it will play catch up with native. It can be seen in the number of issues opened on flutter project on GitHub [1]. Hopefully there is some support from different platforms so it remains reasonable choice and perform well compared to native.
Also it’s declarative UI paradigm is good and even SwiftUI is doing the same.
I had concern about this project earlier although personally I looked at Dart just because it’s developed by Lara Bak the person who transformed google by giving them V8 engine in chrome. Earlier dart could not take off because no one wants dartvm in browsers except chrome.
It might not have succeeded in replacing JS from browser but Flutter is dart’s killer platform and it is very much focused now on becoming a language focused on user interface programming. So I think dart will survive beyond google.