Seen by people who understand nothing about either language then? The vast majority of Scala developers have nothing to do with frameworks that are "adopting" Kotlin. What Google does with Android is completely irrelevant to us. And I'm not sure Google uses Kotlin at all internally.
Kotlin is pretty much irrelevant outside Android, and even there only because Google most likely will never bother to move beyond Java 8 and Kotlin is the Android's Swift, regarding language replacements.
Dart is being positioned as a cross compiling, Android and iOS (but not web) development language with the Flutter platform. It very much seems like a replacement for Kotlin's usage on Android, but only if you are also switching to this UI framework.
It has a very long road to travel regarding OS APIs and the Android team evaded the question at Google IO about what was their opinion regarding Flutter.
Additionally, according to the Chrome team, also at IO, the way to do iOS and Android development is via PWAs, not Flutter.
We're using Kotlin in our backend and pretty happy about it. It has support for co-routines and great syntax, it's lightweight compared to Scala and IntelliJ plays great with Kotlin (no surprise as both of them are from JetBrains).
I won't even mention the learning curve, we started learning Kotlin using IntelliJ's support for converting Java files to Kotlin initially and then it took only one week to learn about the details thanks to its documentation.