Julia would have been the proper answer given the target community.
Naturally with Lather on board, it is Swift all the way, even though its support is WIP on Linux and nonexistent on Windows.
As for Kotlin/Native it is very imature, with incompatible memory semantics between other variants, and to be honest I don't see Kotlin ever taking off outside Android.
All the work that Google did around NBU (Next Billion Users), accessibility and Android are useless using this initiative.
They should have not chosen Swift. Kotlin Native would have worked equally well with day zero targetting for Android
https://resources.jetbrains.com/storage/products/kotlinconf2...