Earlier quoted context omitted.
How come? What's so bad about dart?
The last time I used Dart, it felt like the worst parts of C# + Java put together somehow. The type system was verbose yet relatively weak in comparison to something like Typescript, it'd already been rewritten once (which isn't a bad thing), and it was almost unusable outside the platform (I remember trying to write tests for something using sqlite.dart and then realizing that you just... couldn't). Flutter is an am…
Another thing is Dart is JITed, AOT compiled as well as compiling to JS and WASM. Very few languages can do all 4. JVM ones can't, so no Kotlin (we'll see how well Kotlin Native works), and V8 isn't AOT so no JS or TS either. Only alternative I can think of is Lua.