Serialization support has been coming for years, I lost patience.

Otherwise, yes, some support for expressions, some support for immutability, no support for optional semi-colons, no privacy modifiers so "_" littered everywhere.

I just found it to be an exceedingly ugly language when I used it a couple of years ago. Yes, some more pleasant modern functionality has been bolted on since then, but it's unfortunate that Dart was chosen as the backing language for Flutter, which is an awesome mobile framework.

Serialization has always been possible via libraries, so most people were doing fine with that, what is coming is native serialization support, but in practice it will be functionally the same, ie rather than you running build_runner, the compiler will do it for you. I'm not sure what you used but that's what you were hung up on, there were always ways to solve it.

Dart is a pragmatic language, it has everything you need and has a lot of benefits too, such as sound null checking (very few languages have this, Rust comes to mind), JIT and AOT support (Javascript / TypeScript such as for React Native doesn't, and Kotlin is just getting there with Kotlin Native but it still has a lot of issues), and now more functional programming concepts with algebraic data types via sealed classes and pattern matching.

What language would you have chosen when Flutter came out circa a decade ago, or, we can be even more charitable and ask what language would you use today if you were to implement Flutter? I'm curious because everyone has their own ideas but they all don't work for one reason or another.