i'm trying to understand the delta between Kotlin Native and Scala Native. After trying both I get the feeling Kotlin is going for a pragmatic approach with language support but not necessarily std lib and JVM libs, by which it is minimal close-to-metal (binaries are around 400kb), and Scala is going for 1:1 match between JVM and native (binaries are around 4.4mb).

Kotlin/Native is intended to be "Kotlin for Native development", i.e. no Java legacy is brought, good interop with native libraries in C/Objective C, memory management doesn't force GC etc. So your intuition is mostly correct.