Combining the best parts of Java and JavaScript isn't exactly something to boast about. Dart lives and dies with the Flutter framework. Other than that it's not doing anything special. Not terrible but also not a significant improvement.
Same with your second point. I made a big point to explicitly say I think that right now Dart is very underused and has a huge potential outside of Flutter. Quoting that back to me as though it was something I hadn’t considered is equally as confusing.
Then I moved to Kotlin + Jetpack Compose, and I don't see the point of Dart anymore.