Hi Victor, Thank you for your response...
It means, lets say we have a custom list in our common main (Kotlin) such as "class ShinobiList(override val size: Int) : List<String> {...}"
We cannot access it in our swift part of the project.
i.e we can not create any object of type ShinobiList.
Hope I was able to clear any ambiguity in this.
I will update if i find any better source.
here is the exact source: https://kotlinlang.org/docs/native-objc-interop.html#unsupported